I also work in typescript a lot and it's the obvious comparison/competitor there. While it has objectively "won" it's so so much worse than rescript. Its type system is much more complex, untrustworthy inference, and ultimately is still unsound lol. Ocaml's type system is truly a wonder. Extremely practically helpful, complex enough to express anything without becoming a full blown language in its own right like eg typescript and haskell.
Rescript compiles to very reasonable js and writing bindings is not particularly exhausting once you get the hang of it. I've been using it for a number of projects including completely irresponsible cases like deno fresh and it's been wonderful. What typescript could and should have been.
The more worrying thing is that fresh uses preact while rescript explicitly uses react and so far doesn't have a way to change it. I just overrode react in the import map to link preact instead. This is frightening and fragile, since the interfaces aren't guaranteed to be identical. But it's been working fine on a personal project for a few months now.
And for no good reason (pun not intended).
And they were doing quite well, and influencing OCaml in good and meaningful ways (like improving error reporting).