More anime is being created at a rapid pace so you get a lot of garbage coming out and good ones at the same time. The stories feel like they're cut from the same material too which is annoying at times.... Or you get anime based on light novels but dont pursue finishing the series.
In addition to all this, animators and their companies receive more money from merchandise since people just watch online nowadays. There is also a debate on whether anime should be on sites like kissanime/gogo because the animators are not making money (but free advertising).
I can guarantee that there is more good anime out than before, its just when you are churning out more theres bound to be more garbage out there as well as the good stuff.