Or you could also install the Fennec browser, install the ublock extension, go to the desktop version of youtube and click on the install PWA button to install the mobile youtube PWA, which will be affected by ublock.

That's just a shortcut to youtube.com on Firefox/Fennec, ReVanced (revanced(dot)app) is a much better solution.

Yeah but I really don't want to install any GMS-related stuff on my phone, not even microg, I don't want to have services hanging in the background wasting RAM just because I sometimes watch YouTube :)

Fair