ReScript is better described as a descendant (and fork) of ReasonML aimed to fit into the JS ecosystem. In contrast to js_of_ocaml, ReScript prioritizes interoperability with existing JS code and APIs over interop with existing OCaml code, whereas js_of_ocaml takes the opposite approach. So people looking for an improved version of JavaScript or TypeScript should probably choose ReScript, but people who are porting an existing OCaml program might prefer js_of_ocaml.

There are a few missleadings in your message:

ReScript isnt a fork of Reason, jsoo focuses only on compiling all OCaml and allows JS interop

Reason with Melange is a viable option for JS/TS devs.