YTBShortBlocker от Sohukia

This extension just remove the pannel from the DOM so it is no longer visible. Anyway, you can still access the Youtube Short by going to the address https://www.youtube.com/shorts
It should work but do not hesitate to send me an email at sohukia@duck.com if you experience any issues.
Source code under the GPLv3 license available at github.com/sohukia/YTBShortBlocker_extension.