Even still, this doesn't mean anyone should drop what they're doing and migrate all their code to Rust! If you're a Ruby dev (especially if you do Rails) and you're making a living churning out apps with your good old friends like Devise, RSpec, etc. Rust is probably not the thing that'll really wow you. It _can_ do web, and do it REALLY well. But the experience is very different. (Actix/Rocket)
I think this should be phrased differently. There is a minor bloom of zero-allocation web frameworks in go and java, and probably a few others, which blow their peers out of the water and are horribly not at all idiomatic usages of the languages.
They can be very fast, but the performance cliff for using idiomatic code is very significant.
Does idiomatic rust perform VERY fast? Can it be both very safe AND very performant? I think the answer to both of those is yes, but I honestly haven't used it enough to know.
I'm not a C programmer, but I think Rust can fit almost everywhere C can fit.
Honestly I kind of cringe at the "do everything in rust" crowd, if you need to, say, write an API, you can just do that in Python or Ruby or Go, 99% of the times the performance penalty won't matter and Rust is just a very complicated tool for that job.
But it single-handedly reopened the discussion on high performance, safe(r) languages, and I believe that's a very good thing even though I don't use Rust day-to-day. Projects like Zig are in a sense following in the footsteps of Rust.