As I feel this strongly, I love that the W3Fools site is so awful looking. It's what you get from a bunch of people who are more eager to say what they don't like than ponder why, in fact, W3Schools is so popular. The W3Fools site speaks for them.
Re: W3Fools – A W3Schools Intervention
#11MDN is the usual academic freakshow that is official documentation. W3Schools is a genuinely useful resource for people just getting going. I appreciate correct use; I am a fan of the MDN site. But those who lambast W3Schools are grossly out of touch with the needs of new developers.