Hnn, for me, the enjoyability of either sport really depended on the crowd I'm currently with.
Somedays you'll have everyone co-operating and going out with some sort of tactical plan, other days you'll have no co-ordination, everyone doing their own thing and waiting till break to look pretty standing around or to pose for pictures.
It's honestly a mix of player mentalities here. I could have more fun playing paintball with a bunch of people wearing jerseys and pink markers, than playing with airsofters who are too afraid to get a little dirt on their pants, the same could be said in reverse, don't get me wrong.
Concerning airsoft and paintballs raw content alone, I'd most definitely side with airsoft, minus the difficulty attaining them.
My reason however is almost solely based on the appearance of the weapons, which in itself, is almost possessing degenerating mentality to the players who are apart of the sport. Airsofts realistic appearance appeal alone almost seems to give birth to "chairsofters". Which tends to result in the lack of enjoyment from certain games I have attended where the airsofters were undermined by the chairsofters, or people who just seemed to be there for photoshoots.
As for the maturity of the crowd, airsofts crowd in a sense is more "mature" almost solely based on the age restrictions of those who can attain the guns, which in a good thing. If paintball were as restricted to age like airsoft, you'd see the same thing there as well.
Just trying to bring out some balance here though, I can't help but feel obvious vibes of biases, but better here than in a paintball forum, because you don't find many ex-airsofters who turned paintball, at least some people here have actual paintball experience.