I have only superficially tried it (I'm more of a messy .txt files everywhere kind of person) but https://github.com/IgnisDa/ryot sounds like what you are looking for

For strictly managing a personal reading list, check out my project Booktracker. It's meant to be a sort-of goodreads alternative, and it includes the things on your wishlist like metadata fetching, priority, rating, etc (with lots more coming soon!).

For an all-in-one reading/watch/tracking solution, I know a lot of people really enjoy ryot, but I haven't had a chance to play around with it too much yet.

iOS notes app with iCloud 🥹

Is there anything out there like this but just for YouTube videos?

not self hosted but I really like Trello

Audiobookshelf.

I use a todo app for this. I have a Read/Watch list and just add things there.

I like this because it's super fast/easy to add something, I can sync todos to all my devices via CalDAV, and I am regularly reminded about them when I use my todo list. :-)