That is true, but there are a lot of risks associated with transpiling completely different languages that are not there when using TypeScript. For example, if TypeScript ever goes away, you simply transpile it to Javascript once (i.e. strip away the explicit type annotations) and continue to work on the resulting Javascript - in a different language, that would be a complete mess. Furthermore, TypeScript integrates really neatly with the rest of the Javascript ecosystem (because it's just Javascript), saving you a lot of hassle and lock-in.

Reducing all that to "but it has to be transpiled to Javascript" is a simplification that doesn't help in highlighting potential concerns associated with transpilation, in my opinion.