I certainly get the "youtube is ruined" vibe especially from the home page and all the "trending videos" etc, which exhibit much of what you describe. Seems like a certain golden age is in the past.
That said, I often use youtube for music and last night I was watching performances from The Prodigy - a band I've always liked, never seen, and it was glorious to be able to watch all sorts of live performances, on my big projection screen in glorious surround (upconverted) sound. As annoying as youtube can be, I still find it extremely valuable.
Youtube is much the same as the overall internet; 98% worthless filler and 2% useful. As the overall volume of content increases it just makes it harder to find actual useful information. Like searching for real product tests and reviews and just finding page after page of "here are links to Amazon where I get a kickback, but I haven't tested any of these"
Most of the time when I go to youtube I use a private browser window (and VPN) and its standard, no viewing history, recommendations make me truly sad for humanity. The number of views that some of this junk gets (and I'm sure many of the views are the people swerving around on the road in front of me).
Unfortunately, the useless crap gets views so that is what people make. With instant access to analytics they make each subsequent video with more of what I think is stupid because that is what gets views. I think it is required that every audio channel makes a video about Bose.
Look at 5 minute crafts, Ann Reardon from How to Cook That has shown that most of theirs are staged and best case don't work, but worst case can injure or kill someone yet they have exponentially more views than she does. And when she contacts youtube to say "people have been severely injured trying to do what is in this video" and includes news stories about it; youtube says it is fine because they are making loads of money off all those views. There is actually
a video from someone about making a phone charger that is a solid block of metal from a mold with plugs shaped in it that can plug into the wall.
There was an old MadTV skit where the actors of a sitcom were connected to devices that would shock them if the audience didn't like where the story was going. By the end, the girls were all in bikinis playing volleyball in the living room and if they even talked about stopping they got shocked. In most cases Youtube's instant feedback has gotten us the most vapid entertainment possible.
Somehow, somewhere enough people find Andrew Robinson making his faces like he's talking to a confused child and Darko looking like he is lecturing his girlfriend on which way the toilet paper should go for the 20th time to be endearing.
Possibly even worse though is when I go to youtube when they can see a viewing history and it is
like this. You watched one video on this so here are 20,000 more!!!! It finally made sense how seemingly sane people I know become fanatics about things; all they see are videos about how ants are really government controlled robots sent to eat your sugary foods before you can.