I think that it’s more of a type of content issue rather than the method of learning.
Think online university lecture vs a random dude doing crazy experiments on YouTube
Sure, the lecture covers more content and does it in a more comprehensive way, but you will probably still learn some stuff from the crazy YouTube dude
Specific forums for certain things are still the best.
I have an Aprilia motorcycle from 1999, and the Aprilia forum has 20 years of info, discussion, and advice on that specific motorcycle.
It is also a bit surreal seeing someone reply to my question and see that they joined the forum itself back when I was less that 1 years old.