For YouTube is extremely difficult, people are very used to it, and they are not moving to other platforms when there are decisions clearly against the users as they depend entirely on the creator’s decision (and they will not earn as much money on other platforms… They are still “workers”), it is not as easy as leaving Twitter and Reddit for Mastodon and Lemmy since in this case their creators are the community of users themselves.

There is also the problem of needing a huge storage to save the videos, unfeasible for an open source/FOSS community project unless the rates of adoption are enormous enough and everyone contribute/donate, or at least until we start using more efficient codecs and video compression.