One of the bad things in tech is that reputations stick and people are too quick to bad mouth something because of what it was like 10-15 years ago.
I occasionally used that site at least 20 years ago. It seems to me that it serves the same audience as it did back then. You can quickly find useful pieces of information when you need them.
I don't get where did the bad rep come from. Did they show inaccurate information at some point? I never noticed that.
What I did notice is that people are eager to compare them to MDN any time they are mentioned. Even the wikipedia page about them says "MDN Web Docs – similar website".
This is obviously my personal experience and I could have missed something.
There definitely were problematic articles on the site, and its biggest contribution to my career was probably teaching me to cross-check my sources. There's a list of problems and nitpicks here[1] - apparently all of these were fixed over the years, hence why it's archived.
[1] https://web.archive.org/web/20110412103745/http://w3fools.co...
Yea, they did. There was a massive campaign to get w3schools to fix their docs because it was out of date. The site is still alive https://www.w3fools.com/ but updated. But check out the wayback when machine to see about the errors.