Indeed. But looking at the GC improvements in Go 1.8 ("typical" GC pauses of less than 100us), the set of cases where you can't use the language might be shrinking significantly. Now if only they could turn that in some sort of guarantee...
GC pauses are not the only reason to use Rust. Rust is not "little Go" that you reach for only if you don't want GC. You might want package management, data-race-free concurrency, a mature optimization framework, runtime-free operation, concurrent data structures, fast C interfacing, etc. etc.
One rule of thumb that a lot of people don't realize is that if you aren't maxing out your sequential performance, your parallel multicore algorithm usually loses to an optimized sequential one. The reason is simple: parallelism introduces overhead, leading to guaranteed sublinear speedups. Compiler optimizations, on the other hand, frequently result in multiple factors of improvement.