You can take a look at the actix-web repo, which has been wiped. A message has been added:
See this comment at GitHub: https://github.com/actix/actix-web/issues/5#issuecomment-575... — it also links to a mirror.
What does it say that I wouldn't be surprised one iota if "far, far, far over the line" included death threats? Nobody should be expected to continue to contribute in a community with that kind of vitriol pointed their way.
EDIT: Even if all "far, far, far over the line" means is personal attacks and not death threats, that is still not simply criticism, and it's still far beyond what someone should be expected to endure in the name of "open source".