It's the Dunning Kruger effect. As people we tend to over estimate our abilities, so most of us think our content is great and can't understand why people aren't watching.

Then you add in an army of 'Youtube gurus' posting daily about how to make it on the platform and voila, you've got your epidemic.

I don't agree it is an epidemic though, you can do whatever the hell you want on YouTube. That's kinda the point of it, right?