I think he and I suppose many OS developers are sick of the constant calls to rewrite their OS in the new wonder language. Rust has had the hype train jacked (check all the threads on HN with 'just rewrite it in Rust').

He has had much the same criteria for years. Do the work to prove it. I've often thought it would be interesting to map out the OpenBSD userland and figure out exactly what the work would be.

The frustration is fair and understandable, but his characterization of Rust is wrong IMO.

Side note, has anyone read a Java textbook? They are notable for not being able to go more than a page without extolling Java's virtues in a way that is repetitive and annoying.

(My experience with Rust textbooks was not like that. They tend to explain the drawbacks of Rust's "radical wager" with the stipulation that for the authors, the payoff is worth it.)

Theo often sounds like that if somebody is using "handwavy" arguments.