I don't think such a feature is quite as difficult as one might think. The use case is for repos that are completely abandoned with an actively maintained fork,

I don't think such a feature is quite as difficult as one might think. The use case is for repos that are completely abandoned with an actively maintained fork, so you can be super conservative with the time frame in order to limit the possibility of abuse. Don't allow it for any repository with any activity from its owner in the past year, and give the owner something like 3 months from the time the request is initiated to refuse. If they don't respond, then the repo has been untouched for a minimum of 15 months. At that point, the requester gets their fork marked as the "canonical" repo, with a banner on the original repo informing people that it is unmaintained for X months and directing them to the maintained fork. Thereafter, if the the original repo's owner ever logs in, they could have a button on their repo to remove the banner, or alternatively confirm the transfer of maintainership (after which they can no longer take it back). In any case, the frequency of this kind of thing should be rare enough that it also would be reasonable to require approval by a human at Github for each one. Anyway, the above is one possible concept for such a feature that I think would be pretty resistant to any kind of abuse. But I'm not necessarily arguing in favor to this specific concept. In fact, given how rare such events would be, the most expedient "implementation" of this feature might simply be a dedicated email address and instructions on how to write up such a request for manual review, along with a stated policy of the minimum period of inactivity before a repo is eligible for such treatment. But my overall point is that with abandoned projects, I think you can slow down the timeline for transfer of maintainership to the point that abuse of the feature becomes essentially impossible.