Compile times in rustc have been steadily improving with time. Every release doesn't make every workload faster, but over a long time horizon, the effect is clear. Rust 1.34 was released in April 2019 and since then many crates have become 33-50% faster to compile, depending on the hardware and the compiler mode (clean/incremental, check/debug/release).
In addition an alternate debug backend called cranelift is being developed. The debug compile times are up to 50% faster than the LLVM based backend.