Out of curiosity, are you filtering out shorts because of YouTube's terrible Shorts UI, or solely because of shorts' content quality?

For myself, I've curated my recommendation algorithm down to the point that I don't mind the shorts I get recommended, they're generally from content creators I like anyhow, or content creators that use shorts as their primary medium in ways I'm generally OK with, but the UI is trash. For some reason, I can cast normal videos to my Roku, but if I try to cast a short, it cancels casting, quite explicitly with a popup saying "hey this is going to cancel casting, are you sure?". But the Roku YouTube app is perfectly capable of navigating to a short in the UI and playing it.

And no matter how much I curate the algorithm, the thing that it wants to play next in the Shorts UI is effectively random to me. Not once have I ever seen one that is even a decent recommendation. Maybe I'm hitting some weird edge case because I'm having the opposite problem some people report; Shorts aren't horrifically addictive and I can't stop scrolling, I can't start. The recommendations in my feed are OK but the "next short" is uniformly terrible for me.

That's why I try to prune them down a bit.

I keep up the fight because as a recent article noticed, YouTube is still a unique video service with an astonishing amount of high-quality content from small creators, fascinating math videos, how-to videos, etc. I'm more-or-less winning the fight with the algorithm at the moment and it still often turns up interesting things. But it is a constant fight to keep it from becoming a lowest-common-denominator feed. Goodness help you if someone links you a YouTube video of a cat being stupid or anything political, get that watch out of your History before you forget.

Most channels post just clips of full videos on Shorts, it's not original content.

I've already seen the full video, I don't want to see clips of it again.

Also 90% of my RSS reading is done on a desktop/laptop and it feels "wrong" to watch 30 second vertical shorts on a 32" display :D

Not OP, but because IMO shorts are mentally harmful. They're the mental equivalent of transfats-heavy foods.