Slower compile times are a small price to pay for memory safety and much higher productivity.
There are trade-offs, rust makes one, use it if it makes sense but these comparisons are just pointless. This whole thread is filled with such arguments. Sure use OCaml, Haskell, Go whatever suits your needs. But let's not pretend that they achieve at compile time what rust does.
Somebody is complaining about compile time, somebody says GC alternatives exist. No, if you are getting into Rust you pretty much know the trade offs. It's on you if you choose Rust somewhere where a GC, REPL providing alternative would have been enough. The miracle of Rust to me is that I usually find Rust high level enough to not have to bother with the alternatives most of the time. I would write my UIs in flutter and my web frontends in TS. I am under no illusion that a GC language would not be more productive in most cases.
Are you talking specifically about the memory use of rustc vs. ocamlopt? Or do you mean that rustc is faster than ocamlopt at compiling a similar program? Or are you saying that rustc does more work than ocamlopt because of the borrow checker?
I was asked a few weeks ago, "What was the biggest surprise you encountered rolling out Go?" I knew the answer instantly: Although we expected C++ programmers to see Go as an alternative, instead most Go programmers come from languages like Python and Ruby. Very few come from C++.
We—Ken, Robert and myself—were C++ programmers when we designed a new language to solve the problems that we thought needed to be solved for the kind of software we wrote. It seems almost paradoxical that other C++ programmers don't seem to care.
They can help, but I am well aware of which kinds of bugs existing C tooling cannot catch. I still take issue with your opinion, which hold through this thread, that claims that productivity gains from not having to track these down necessarily outweighs Rust's compile times.
Coming from C++ rust's compile times don't feel extraordinarily long.