Rust doesn't have a scheduler.
The issue is the false assumption, that the remove operation can safely be done without taking a lock. This can be done in some specific data structures using atomic operations, but here the solution was to just take the lock. The same thing could have happened in a C code base but without the unsafe block indicating where to look for the bug.

Yeah, I'm not saying it's rust's fault. Restricting this to unsafe makes it a lot easier to reason about where such problems can occur.

I just don't think anyone should give the impression that rust's memory safety is not about race conditions.