You do? It does ok if I'm watching something technical or some reviews. It's laughably bad at music and wider interest content such as a documentary. If you hit a music track, 50% of the recommendations are the same damn track in degrading levels of quality, 30% the same band. The 10% that's left for other artists are normally a really bad connection to the mood. The last 10% lately is taken by awfully bad match, clearly sponsored, junk though never identified as sponsored.
Most of the time I'd like suggestions in the same genre or mood of music. If I've just watched an upbeat rock track why not suggest other upbeat rock tracks? Last.fm radio was superb at this, for years, until CBS destroyed it. So it can't be that hard.
I think the only times I use the sidebar is if the vid I landed on is terrible quality or a bad hit.