It’s kind of a shame, because Github keeps giving me fantastic ways to toot my own horn, but I can hardly do that if I can’t improve on their numbers.
Between the git hosts things move around based on available space, IO pressure and whether it’s been recently accessed or not (spinning disks are far cheaper these days). Theoretically there will be a point where the routing becomes a problem, but probably not until there’s several hundred git hosts (I’ll probably have bandwidth problems before that happens).
I’m not sure what the largest git repo is that github has, but I can theoretically keep repos up to 1TB around (plus a sheer unlimited number of forks for the same). I imagine the API’s get problematic before git does at that point (e.g. shuffling data around is much harder than storing it).