It's like all of BuckleScript and parts of ReasonML is now ReScript. Except BuckleScript has a new C-like syntax unlike the ML syntax that made BuckleScript BuckleScript as opposed to ReasonML.
Basically Bucklescript have forked their own (very similar) syntax from ReasonML and branded the whole syntax + Bucklescript + compiler package as ReScript. I suppose the goal is to eliminate the confusion of having so many moving parts and unify them all under a single ReScript brand.
Thanks. I guess the thing I didn't understand was where this leaves Reason: what is left under the Reason banner? But a fork would explain the overlap.