From a quick read it seems pretty obvious that the author doesn’t speak English as a native language. You can tell because some of the sentences are full of grammatical errors (ie probably written by the author) and some are not (probably AI-assisted).

My guess is they wrote a thank you note and asked Claude to clean up the grammar, etc. This reads to me as a fairly benign gesture, no worse than putting a thank you note through Google Translate. That the discourse is polarized to a point that such a gesture causes Rob Pike to “go nuclear” is unfortunate.