I spent a decent amount of time making a nice web application to wrap up the functionalities of yt-dlp, makes it really easy to follow content through Jellyfin!
Have a look if you have the chance, I think people could make good use of it: https://github.com/MattMckenzy/ToothPick
It doesn’t directly integrate with Jellyfin, but it does store the media in a directory and file format that works well with it. I use it to subscribe to media playlist pages that yt-dlp supports and I get them added to Jellyfin automatically.
I was considering adding pictures when I have the chance, I’ll see if I can do it later!