In keeping with the topic, kind of, I just have this to say:
90% of music is crap.
This is because 90% of everything is crap.
OK, maybe only 85% of jazz is crap and 92% of hip hop is crap and 98% of country is crap, but it all averages out to about 90% crap.
It has always been this way. It just seems like there are more crap bands now than in the past because everyone has forgotten the crap bands of the past.
A corollary -- 99.999999999% of internet posts are crap.