There is crap software for every computer ever made, thats nothing new. Ask 1000 PC users what their favorite cad, word processor, data aquisition, video editing app is and there will be more then 2 programs in each category.
Computers platforms like the amiga didnt die out because you couldnt find hardware to buy, its because nobody was making software for it anymore. There are enough PC supporters to allow some "cheasy" 3rd rate apps to make their developers profit so they stick around and some thrive. Some of those cheasy apps get better over time, some of the top apps get crappy.. but the developers are healthy enough to keep the platform going over the long haul.. which is something apple has to worry about when huge companies like adobe start jumping ship from their product line.