Which turns out to be exactly what you need to be productive writing software. People who obsess about type systems and try to solve everything within them create a whole new bag of problems.
We're getting into the domain of opinion here. I would say TS is different enough such that it's two different languages.
Programming with type checking and programming with plain JS is really different. A programmer without experience in types (ie plain JS) won't be able to pick up types that that quickly on average. Things like enums, Generics, sum types, product types, recursive types, really change the game by restricting what functions can do.
> Things like enums, Generics, sum types, product types, recursive types, really change the game by restricting what functions can do.
If only that were true. The reality is that if you can write it in JS, you can add TS types no matter how horrible or anti-pattern the code happens to be. The constructs you mention don't restrict what functions can do in any way at all.
> A programmer without experience in types (ie plain JS) won't be able to pick up types that that quickly on average.
The average JS dev seems to have a Java/C# background where types exist. Further, they seem bent on slowly transforming JS into one of those languages.
