>primarily because the structural typing of TS makes thing much easier to refactor compared to the nominal typing of Java.

That's interesting. This year I switched from server-side Java to server-side TS and I find that refactoring is incredibly painful when compared to Java. I think any productivity gains in the greenfield portion of a TS project are quickly offset by the pain of refactoring and debugging during maintenance. It's really disappointing, as I quite like TS.