“anti-FOSS to me to require a Microsoft account for a fediverse request, so I’m posting here and hoping for the best.”
It’s more about efficiency and prioritization of actions than anything else.
Could the devs spend time and effort migrating the code to another repo, such as Codeberg? Yes. Would the benefits be worth the time and effort? Debatable.
You can just create a throwaway account for GitHub. Not ideal, but devs have said multiple times that they don’t have the time to track feature requests elsewhere than on the GitHub (and it makes sense)