They didn't have to but Anthropic chose to open their mouth and announce their "reasons" for the rewrite. Don't blame anyone but Anthropic for this, they didn't have to try to justify it, but they decided to anyway.
Sure that had to justify it, people were writing all sorts of posts about how Bun was no longer trusted since it was rewritten with Rust.
Bun's post was explanation of that process that was (IMHO) pretty reassuring in that the new version of Bun is not 100% garbage.
(Now in the ideal case that post would be released before, or at the same time as, rust-based source code on github... Then there would be much less drama)
Exactly. The people criticizing the rewrite for the most part are just trying to exert power from the wrong end of a parasocial relationship. And then they get upset when no-one takes them seriously.