ICE aren’t growing much in size and are getting more and more efficient. Why not make them air cooled? Porches used to be aircooled, and those were performance cars with the engine in the back. I would imagine having an engine in the front might be easier to cool, no?
I would not say they are less reliable. Air cooled 911s have all been much more reliable than the 996 and 997 generations (the first two watercooled generations). 991 and 992 are too new to tell yet but I don’t think they will be that good either.