You can learn on anything. Dont sweat it so much. The board impacts in a way only because youll have a certain skill set from it based almost entirely on the forgiveness of the board.
Let me explain.
A soft board will let you get away with lots of things, its not for nothing its the default recommended beginners board of choice after all. Youll get a lot of satisfaction form it, and youll also get a lot of confidence from not face planting on your first box. As you progress though and start riding it more aggressively youll realise its washing a bit more, and youll have to reign it in a bit. This means you wont charge so much because the board just sint very forgiving in those conditions. Indirectly youll find the board being pulled towards what its made for because it IS forgiving in those conditions - namely park. Now nothing in the universe says you HAVE to ride anywhere else so you could ride it forever and ever with no problems... and anyway its not that you CANT ride it outside park, its just that it wont be as fun (and by fun i mean FORGIVING) as your medium flexer resort cruiser board.
Your medium flex resort cruising board is your jack of all trades. For the most part the trend has gone to reverse camber or at least hybrid on these (sl-r, indoor, custom for examples), possibly to gain the effect of having the soft playful buttery board that also charges. But the normal camber profile still exists, so again you have a different type of ride and forgiveness. Ill stick with the reverse though because thats my experience with these decks. They tend to nail almost everything you want to play with. They will turn your resort into a gigantic playground as youll find yourself flying up walls, bonking off everything you see, and bouncing off every bobble you find. Theyre all about FUN.
But fun comes at a price. The time youre busy spent bouncing and dicking around is of course time you could be getting some more serious (but boring) technical skills. Again, this isnt universal, you could just be practicing your carving on these decks as much as any stiffer deck - in fact if you have the normal camber profile, you probably will be. But again, the board will kind of pull you inadvertently to where its most fun (and thus MOST FORGIVING) for you. This will be in freestyle resort cruising. The nice thing about these decks though is that the pull isnt quite as strong as say a noodle may pull you into the park. Though the boards at the peak of its fun doing tricks all around the resort, its still capable of bombing the mountain or going deep in the powder (at least, my sierrascope is).
The single best feature about these boards is that they give you a taste of everything and dont force you to commit to a style of riding before you even know what you want. For me, i cant think of a better beginner board. Maybe the one draw back is they tend to be slightly more pricey, they also tend to come with sintered bases, which require a bit more care and maintenance than extruded bases. Though that of course isnt a universal either. Also, if you do go reverse camber on them, they may be fun and all but they can and do wash. Its all about tikering though, so either throwing down a camber model or in fact sizing up will probably give you more stability and stop the board from washing and rough riding over chop (the scopes two big weaknesses).
The camber version means youll lose a bit of the buttery playfulness, and youll maybe be catching a few more edges, but again the flip side of this is that pain is a great educator. Youre riding will probably end up a little tighter than if you went reverse camber for the one simple fact it needs to be. Which brings me to stiffer boards.
Freeride decks are demons for beginners. I know, thats what i learned on. Admittedly i didnt pick it up until around day 9 or so which im very very thankful for. I cant imagine starting from scratch on one of these. Id have probably quit after the second or third day of scorpioning.
As i say, they are demons for one simple reason. They are decks that are meant to be riden hard and aggressively. You just wont have the skill to dominate this type of deck for a while, and it will spank you for it. BUT as with the camber freestyle deck above, after a while on one of these decks, your riding is going to be TIGHT. I mean seriously tight! and the reason for that is simple: if you ride this board loose, youre going to get a smack, so you stop riding it loose. So while your mates are busy doing presses and dicking around you will be BOMBING the mountain. They may try and keep up, but its not going to happen.
After a year on a deck like this, youll find inadvertently youve become a bit more of an aggressive rider because that thats where the board kind of performs its best (and most forgiving). Youll find yourself way more comfortable with speed, steeps, and all round charging and youll barely ever wash (it does happen though, i wouldnt suggest otherwise - everyone washes just like everyone catches an edge). Youll probably start digging some serious trenches as well and will laugh at your mates terrible fat slidey tracks while you gloat about your beautiful pin like trail. Still, your mates are going to wet themselves when you try to ride boxes and faceplant on every one of them. Youll probably grow to hate the jibby area of park and stay well clear of it
Also, there will come days when you look on in envy at people buttering the mountain and wonder what it must feel like to look steezy :'(
The point i guess is that at the end of the day, every board comes with something its really really forgiving at and something its not so forgiving at. You wont wash on a freeride, you wont catch an edge on a reverse camber, you wont get pigeonholed on an all mountain freestyle, but they all come at a bit of a cost somewhere. I mean, you CAN ride any board anywhere, and if you do, you wont ever feel that cost in truth (because youll learn how far you can get away with stuff before you reign it in): You can charge on a noodle, you can hit the jib park on a freeride, and you can specialise on an all mountain, its just that you may one day end up riding something like a scope after riding your freeride stick and realise that a lot of the stuff you wanted to do (but found pretty taxing on your face and tenacity levels) is suddenly WAY easier on your new deck. In fact, it almost feels like cheating. So instead of taking out your stiff freeride board, you have a blast just messing around on the mountain on your new resort cruiser.
But then a year later and you start pining for a bit more aggressive ride again... so you buy a new deck so you can start wrecking stuff outside the resort without the problems of washing and chop
I love my scope, but i think ive been influenced despite myself that a softer playful board is nice for doinking around on, but ive become an aggressive rider... and a lot of that is because of the type of ride i learned on.
And if im honest, I wouldnt trade in that year i spent on my artec for freestyle skills even if it cost me my fair share in edge catches and scorpions. Its fun riding a bit looser, but i seriously miss riding aggressively and it took just 1 morning board trade with my mate to realise that. Stick me on a stiffer cambered deck and its like coming home.
As i say, you can learn on anything. I wouldnt touch a freeride though until you at least have the basics down though because youll cry
But after the basics are down the whole world opens up and you can learn (like the serious part of learning, not just learning to link a turn), on anything. Spend your first 5 or 6 times on a rental deck (but try and stick with the same deck or type of deck if you can) then have a little experiment with sizes. Once you feel comfortable then idf think about buying your deck. And for your first couple of years id SERIOUSLY consider just buying an all mountain freestyle board because it wont really push you into any particular style and will give you a taste of everything the mountain has to offer. Plus itll be a while before you find the point where you progress beyond the boards limitations (if in fact you ever do). The other two outliers will make their restrictions apparent very quick. And though you can overcome them with a bit of tenacity, itll still be a bit of a pain in the ass.
Plus of course, the board is serious FUN which is what its all about at the end of the day.