The easy way to do this is to hide them with custom CSS
- Install Stylebot extension for your browser
- make an entry for youtube.com
- enter this css: .shortsLockupViewModelHost { display: none}
Bam, no more shorts.
To be fair, Ublock Origin is a lot more common, and the less extensions the better, so or a lot of people this would be the better way.
Stylebot is no longer actively developed, but the similar (and open-source) Stylus extension is.
Repo: https://github.com/openstyles/stylus
Chrome extension: https://chrome.google.com/webstore/detail/stylus/clngdbkpkpe...
Firefox extension: https://addons.mozilla.org/firefox/addon/styl-us/