for several days now I couldnt load youtube. incognito works though. so I thought it has to do something with my extensions. turns out ublock origin (when enabled) causes youtube to only show a skeleton page (no content).
searched and found this on reddit: https://www.reddit.com/r/uBlockOrigin/comments/167bzk9/youtube_stopped_loading_with_ublock_origin/
Have you done this?
Meanwhile, for a less "ad-full" youtube experience, try yt-dlp: https://github.com/yt-dlp/yt-dlp