It's not about learnability, compile times or anything like that - Go has a high-performance concurrent GC and Rust does not. There are whole domains, problems and the like that are basically unapproachable in Rust unless you're up for reimplementing half of a LISP system beforehand. (And people do - that's what the ECS pattern often boils down to!)

Rust is a systems language (as in C, C++, or Ada), Go is an application language (as in Java, etc.).