Thank you for the explanation. It's obviously not great that this was missed, but finger-pointing now doesn't really help anyone, so I'll focus on what seems to me like the root issue

My impression is that there is an information gap about forked projects that lead to this issue

I'm on vacation right now, but when I'm back I'll try to setup a small site that lists forks of popular projects and maybe some information on when in time the project was forked

Hopefully something like that can make it more likely that these things are responsibly disclosed to all relevant projects