> But it seems kind of random why they picked Rust. I do not think there is anything which makes it particularly good and it certainly has issues.
Like I said, they picked Rust because there was literally no other suitable language. You're avoiding actually naming one because you know this is true. Even among academic languages very few targeted being able to replace C++ everywhere directly as the language was deemed unsuitable for verification due to its complexity. People were much more focused on the idea of providing end to end verified proofs that C code matched its specification, but that is not a viable approach for a language intended to be used by regular industry programmers. Plenty of other research languages wanted to compete with C++ in specific domains where the problem fit a shape that made the safety problem more tractable, but they were not true general purpose languages and it was not clear how to extend them to become such (or whether the language designers even wanted to). Other languages might have thought they were targeting the C++ domain but made far too many performance sacrifices to be suitable candidates, or gave up on safety where the problem get hard (how many "full memory safety" solutions completely give up on data races for example? More than a few).
As a "C++ guy" Rust was the very first language that gave us what we actually wanted out of a language (zero performance compromises) while adding something meaningful that we couldn't do without it (full memory safety). Even where it fell short on performance or safety, the difference with other languages was that nobody said "well, you shouldn't care about that anyway because it's not that big a deal on modern CPUs" or "well, that's a stupid thing for a user to do, who cares about making that case safe?" The language designers genuinely wanted to see how far we cold push things without compromises (and still do). The work to allow even complex Linux kernel concurrent patterns (like RCU or sequence locking) to be exposed through safe APIs, without explicitly hardcoding the safety proofs for the difficult parts into the language, is just an extension of the attitude that's been there since the beginning.
And, it's really funny that GP criticizes Rust but doesn't acknowledge that of course blood, sweat, and tears have already gone into less drastic variants for C or C++. Rust itself is one of the outputs of the solution space! Sure, hype is always a thing, but Rust has quite demonstrated its utility in the free market of programming languages. If Rust was not as promising as it is, I don't see why all of these companies and Linus Torvalds would seriously consider it after all these years of experience. I can accept if C had a valid "worse is better" merit to it. I think C++, if anything, has the worst value-to-hype ratio of any programming language. But Rust has never been a one-trick pony for memory safety, or a bag of old tricks. Like any good language, it offers its own way of doing things, and for many people, its way is a net improvement.