For YouTube, I never actually visit YouTube.com. I view my subscriptions via my RSS/Atom feed reader and I watch the videos with mpv. This has probably saved me many hours I would have wasted clicking through "recommended" videos in the sidebar.
I found this on github: https://gist.github.com/jeb5/da22862e469dea21e873acabb562f63...
Was able to get all of my feeds exported to an OPML file, then imported into my RSS Reader of choice.