as of a month or so ago, my Note 10.1 from 2012 now only loads m.youtube.com in Chrome, despite it being one year older than the Samsung browser built-into it.. the Samsung browser skeleton loads now. I think whenever the thumbnails went rounded corner UX it broke the browser since it apparently fails at drawing them and gets into a javascript error loop in the background. If i go to Google on Samsung's browser and search for specific content under 'videos' it will load the video itself and even play it, but the rest of the site is still stuck skeleton loading, with blank icons everywhere, the player UX also not drawing the rounded corners even if it otherwise works, and pausing the video won't allow resuming, as audio continues but video is frozen at that point. the scrubber bar is also MIA.
Chrome version 24, from literally October of 2013, still works with m.youtube.com, and draws the exact same layout as Samsung internet once did, albeit with the rounded corners. Either they blacklisted Samsung Internet because it's not Chrome and because it's an otherwise AOSP-based browser, or the rounded corner UX broke it. But the fact that even the oldest Chrome version for Android, literally the first version APK works fine, leads me to believe the former.