Waxing definitely seems to help when the moisture content in the snow is higher but once it gets really high, even graphite wax won't do much. Structuring is awesome for not keeping speed in wet granular or slush but if you ride enough, you'd have to get a stonegrind done quite often which is $$$$.
I had a Westmark (rocket base, sintered) in the shop last year to get filled and ground and I rode my second Westmark for that day which was factory brand new. It was a huge difference riding the new board. But then when I got my old board back, it was just as fast as the new one.
You will definitely notice a difference when moisture content goes up and if you board is really devoid of wax. Otherwise, if there's no moisture, it won't make as much difference.
The snow out East has quite a bit of moisture in it so when the sun hits it even with really cold air temps, it actually can help to have a decent waxing done even if it's just a one and done with an all-temp and no scraping or tuning.
And I don't think it's going to help at all against base damage. Base damage is almost exclusively caused by rocks, sticks and what have you. Wax won't stop that.