JS has concurrency (but not parallelism) despite being single-threaded, though.
If you ever put an await anywhere in your code, an arbitrary amount of random stuff might run between the time you await and the time the awaiting finishes.
Same applies to older mechanisms like callbacks and promises.
Race conditions are more rare there because as long as you aren't doing any IO, there is indeed no concurrency, so you can't e.g. get two threads trying to increment a single variable at the same time. They can still happen, though, especially if you accidentally do a partial change to an object, put it in an illegal state, and do IO before you finish that change.
> The vast majority of errors caused by shared mutable state are related to concurrency.
Concurrency, like async-await, you mean?
> TypeScript's type system contains features that Rust's does not have
Sure, and likewise Rust's type system contains features TypeScript's does not have—for example, just try expressing anything close to traits with TS's type-erased generics. Since the feature sets aren't the same, I suppose it's a matter of opinion which type system is preferable. But I know which one is more helpful for me for sure (especially considering the aforementioned soundness issues).
...which is an extremely rare source of bugs. The vast majority of errors caused by shared mutable state are related to concurrency.
> usually
So, not always. That is - TypeScript's type system contains features that Rust's does not have.