There is an add-on called unhook that allows you to disable almost everything on youtube.
I turned off shorts, recommendations, the home page even the comments. Now all I see is my subsriptions page. It really stopped me from wasting hours hopping videos.
It also workes on firefox mobile, I stopped using the default youtube app.
Unfortunately, it doesn't disable shorts from the subscriptions tab. Which is really annoying now that all my preferred creators are making shorts, and it tries to suck me into doomscrolling.
I started using Chrome plugin RYS that does something similar - where youtube functions but recommendations are removed. It's helped consumption dramatically. I'm kinda wondering if I need to do the same for reddit and hacker news where links/articles would work but the mainpage / subreddit pages wouldn't.
But I hate the Shorts features, if I click on only one video, it sucks all my night.
I built a small app for blocking the Shorts features, in this way I can enjoy the advantages without having the bad sides.