For instance a few weeks ago I was stuck on a quest in WoW Classic, so I did a quick YouTube search, 100k+ view video, dozens of likes.
Yeah the video sucked and didn't show anything worthwhile.
But that would be just someone’s personal opinion (or worse). Why should I care? Besides, people discuss things on forums, and a more detailed review is more useful than a simple vote. Finally, it is often not that hard to see whether the presentation or the content is worth your while from the first few minutes of watching it. (There are, of course, some cases when watching is made difficult because of the presenter’s excessive showing their face or gesticulation, or having a distracting accent, but even those do not necessarily deserve being called “crap.”)
Also, why should I care about the algorithm's opinion? IME it's much much worse on average than the up+down vote ratio from thousands of individuals.
They removed the one metric that people had to signal that content is crap. So now people have to trust that "the algorithm" is filtering out all the junk. Which of course we know doesn't happen. The algorithm only cares about engagement, it doesn't care if the content is of good quality or even truthful.