If you want to hide Shorts completely on YouTube, or make watching them a more intentional act by hijacking YouTube's navigation to make them display in the regular video player, Control Panel for YouTube [^0] has options for that, as well as for removing any other sources of algorithmic/recommended videos you don't want, including the new "More videos" in the new video UI (which you can also disable if you don't like it)

[^0] https://soitis.dev/control-panel-for-youtube