Looks like the situation has already been resolved. The commiter was using git-filter-repo in a script which borked his tree by rewriting commits in unexpected ways: https://lore.kernel.org/all/202505312300.95D7D917@keescook/

And his commit access has already been reinstated: https://lore.kernel.org/all/20250601-pony-of-imaginary-chaos-eaa59e@lemur/

woah this looks bad, good on Linus for calling it out