CoffeeScript, for one, is already at least talking about emitting TS [1]. These kinds of changes are vigorously debated though, e.g. [2]. Once ECMA type comments get to stage 4, CS would probably also adapt the new syntax. Other compile-to-js languages that already ship with their own type system like Dart will probably be indifferent to the debated proposal.

[1] https://github.com/jashkenas/coffeescript/issues/5307 [2] https://github.com/jashkenas/coffeescript/issues/5394