I'm among those who hate it... it's worse than change for the sake of change & not being functional, it makes things less functional. The thumbnails under the video are annoying, but now to get more info on the video you need to click a few extra times to minimize your playlist & then click a few different 'more'... then it's squished in the stupid side column. Just frustrating wonky mechanics. The search results now are less useful too in a single column. If I wanted to use an app, I'd be on a phone or a tablet... forcing the app experience on desktop never works. I've reported it via 'send feedback' every day since it rolled out, lol.
That does sound like a pain. I don't inherently hate moving comments to the side, the narrowness actually makes some sense for that and it's a cleaner way to read comments along with the video playing, but things like moving video detail dropdowns from being below the video to hidden in the side as well are a bit much.
yeah, if it were 'just' the comments... go for it. but put the details back under & give a little buffer between the row of icons. it's not like the couldn't make whatever is under the video (comments or thumbnails) independently scrollable...