"I wish shorts would die."I'm pretty confident it will.
What I'm going to say is purely from the user experience perspective and will - for the moment - completely ignore that YT Shorts, as well as TikTok, are basically drugs and should be treated like that. Also, I have no inside knowledge of any of the products working and algorithms, it is just my personal experience as a user trying out both products in parallel.
With that out of the way: YT shorts is terrible compared to TikTok for the following reasons:
1. In my experience the TikTok algorithm adapts very fast.
I usually watch tech but occasionally dabble into music. When I watch piano videos for like 20 minutes TikTok treats me like I was a musician. Back to tech, also very quick. YT seems to adapt much slower.
2. The TikTok algorithm doesn't mess around.
My daughter likes to watch dance videos. As she has no TikTok herself we watch together on my account. Again TikTok adapts to that very fast and treats us like a teenager. But even before the algo is tuned in it never showed me anything inappropriate.
My armchair suspicion is that while TikTok finds a local maximum of what I want and reliably sits there until I nudge it out, YT has the idea to probe me from time to time if another local maximum might be better. This might be good in theory but when it tries to figure out if a latest dance craze video watcher would also like to see some naked raunchy twerking ladies it has failed miserably.
3. The TikTok algo is fine-grained.
Apart from tech and music I watch the occasional extreme sports video and I have my own taste there. I like physical skill but not so much strength. I like bicycle tricks but no motocross. Cars are generally not my thing except for Gymkhana.
This is no problem for TikTok. It is like the sports I don't like would not exist. YT on the other is all over the place with its suggested videos.
The worst thing on YT is that it occasionally shows me videos where people got hurt badly. One of these videos is enough to kill all the fun for me because I can never be sure not to see gore the next time. TikTok never let me down there.
4. YT moderation is terrible, TikTok's decent
My general impression is that TikTok's limits are wider but fairly well-defined harsh lines. YT 's limits are narrow, fuzzy and inconsequential.
5. YT is basically a TikTok rip-off when it comes to content.
Many of the videos on YT shorts are either copies or recreations from TikTok. I believe for videos that use content from the TikTok library it is infringement, but YT seems to look the other way.
Finally, if all of this sounds like TikTok advertising: It's not. I think both TikTok and YT Shorts are harmful products. The later is just lame too.