It all depends on where you want to spend your time. You can be productive on C# up front and then burn a lot of time chasing down performance issues later. You could get super performance with C++ and then chase down memory and security issues later.

Rust has solutions across all the domains from web development, game development, embedded systems, etc. You may want to do more research into what is available for the platform - and maybe spend a bit more time understanding memory management. I mean you had to do it with C/C++ as well and you learned that. You didn't run off to Pascal did you?

Rust has a learning curve, but once you get past that - you can be at least as productive as you can in other languages.