Twitter, YouTube, and many other services have built-in bookmarks and playlists encouraging you to save content for later. I encourage you to try using a third-party service instead of them. Raindrop is a great alternative.
Platforms want to lock you down, and it’s easy to save everything right there, but you will likely end up with an endless stream of saved notes you will never revisit.
The main problem with Twitter bookmarks is that they are not very user-friendly. It is difficult to find the tweets you have bookmarked, as they are not organized in any manner. There is no way to search for bookmarked tweets, making it even more difficult to quickly find the tweets you have marked for future use. And most importantly, if the author deletes the original tweet, you will be left with nothing.
YouTube playlists have similar problems. Yes, YouTube provides you with folders, and you can use playlists as intended, although I wonder how important that functionality is. But if the video is deleted, you won’t even be able to figure out what it was, as there’s no title. And you can’t search through your playlists.