Likes from logged in views do count, the like to view ratio is higher due to that.
A German YouTuber tested it with an unlisted video, I can’t find it as of now but I do find a lot of deleted videos in my liked ones…
Basic theory as of the time of the video is that they want to go against bot views. Short views did not decline, only long form video, and of those the people with mostly desktop views are hit the most.
Edit: found it!
I knew something was odd. I watch youtube without an account and in the past few days, when trying to watch some of my favorite channels youtube prompted me to “lognin to prove” I’m not a bot. This was only for a handful of channels, others seem to work fine.