This is how I develop web software, and I've found it productive and maintainable.

A bonus of this approach is that it clearly delineates what type information is available at runtime, vs what type information is just a comment. (especially useful when working with serialized data).

I also like that it generally means all of the preconditions and postconditions for functions are in a single place (both the prose and the technical information are in the JSDoc comment), keeping the code itself low-noise and boiled down to its essence, and providing a natural place to write example inputs and outputs to guide usage.

As for generic types, I use them extensively, and this is made less verbose e.g. on function calls by using an @type annotation on the function which accepts a TypeScript signature without needing separate @template + @param annotations.

It's awesome stuff, and I'm happy that TypeScript works so well with JSDoc!