It has nothing to do with any of them being experts, and more to do with the fact I spoke to a lot of people about this stuff and they all said 'find something you enjoy riding rather than worrying too much about a specific camber'. Some knew their shit, some probably didn't, but no-one I spoke to said anything to suggest that I'd necessarily develop better technique riding camber.
I originally thought that I should get a camber board for that exact reason you said. I instead bought a Ride Machete (rocker), because it seemed to suit my style of riding and a lot of people had good things to say about it. I personally think I am learning stuff a lot quicker on this board and enjoying my riding a lot more than when I was on rental boards, all of which were camber (at least the ones I rode). (that could equally be because most rental boards are pretty shitty though)
It makes sense really. If you have a board you enjoy riding, you can spend a lot more time thinking about developing your skills, because you don't have to worry about getting shitty and frustrated because the board didn't handle like you wanted/expected it to in a particular situation.
With all the hybrid boards around nowadays I think it makes a lot more sense to think about whether the board will suit your style of riding rather than getting too hung up on the exact camber of the board.