Yes, that's the current state of things. But support for control-flow typing of my above two examples seems like an easy addition to the TypeScript compiler - if that's what you want. Personally I'd like to see JS support for proper pattern matching, i.e. TC39, then TypeScript can build on that.
> But support for control-flow typing of my above two examples seems like an easy addition to the TypeScript compiler - if that's what you want.
The first one is not useful and the second one is nonsensical (as there is no guarantee that there's any relation between #constructor and the type of the variable)