It's a little silly to say "mainstream is crap! Why doesn't the better stuff rise to the top?" It's because people don't agree on what's better.
Or maybe, just maybe, it's because taste and discernment (which are personal values) correlate inversely with access to resources (which is a globally recognized value).
>It's a little silly to say "mainstream is crap! Why doesn't the better stuff rise to the top?"
If it's silly to ask that question, maybe it's also a bit silly to answer it - but sure, lemme throw in my own 2c:
It's because the "compromise" you speak of amounts to human society taking on the role of a half-witted hivemind.
IMO a better question to ask is what's the point of there being a "mainstream" at all? It's not like lived human experience is fungible... is it?