I think it's a red herring. TS's typing isn't the only thing that is true about it, and is not the salient issue here. Were TS merely to force types upon me, I think I'd have few grievances with it.

Yes, yes, I know—it's (2.x) a superset of ES6. But just you try writing Angular 2 code in such "ES6". No, you have to play ball with generics and the full gamut of Java features.