To be fair to your proposal, this is how people manage to keep track of sci-hub, so it definitely work enough (even if this kind of censorship is different from the use case we discuss).
So I guess that also bring another question, on why people would keep that up to date for less important projects than Sci-hub.
Also, another issue when forking/moving is data. For example, git repositories need to be replicated (which is not the bigger problem, as long as you scripted that), but also authentication and identity (which is a lot harder).
Another issue is also there is a lot more things that have the same property as domain names for a project (eg, being exclusive). For example, the naming on pypi/CPAN/rubygems/dockerhub/etc. While people can host them locally (Fedora has its own registry), having a prefix (eg example.org/module) is going to be less convenient than not having (eg just module), and this cause some problem from security issues (name squatting on dockerhub) to fixing consumer (podman ask to choose the registry when I do “podman run fedora”).
it seems like a free software movement wide initiative to get that fixed.