they had a tendency to overheat in hot conditions, and when stuck in traffic. this is because they need a certain amount of air flowing in order to cool properly.
they also weren't very good for heat in the winter.
air cooling is a simpler system, and as such has less to go wrong with it. that doesn't make it better or worse. there are pros and cons to both systems.
personally, i still do it out of stubbornness. the old cell phone games weren't real games. they were less than old Atari games. as cell phones evolved, so did the games. eventually we get into the more modern era, and some cell phone games are more 'real' than older console games were.
i acknowledge that modern cell phone games, are often more of a real game than games we had back in the console days.
that said, i'll still consider them not real games for many years to come. don't worry what other people think. if you enjoy them, play them.
one of my favorite jokes about this is on TNG. i think it's the episode where the bridge gets cut off from the rest of the ship, and Troi is in charge of running the ship. O'Brian makes a comment to Ro about how you can't 'just reroute power from things'.