> They are both TypeScript.

I take issue with this position because this seems to imply "PureScript and JavaScript are both JavaScript" is a true statement merely because one of them turns into the other with tooling.

TypeScript is indeed Javascript, all you have to do is remove the type annotations. They are not code.

TS does have some minor things like enums that need to be transformed and are actual code, but those are very few, and leftovers from early days of TS, and the TS authors regret having implemented them. For many years now the TS philosophy has been that the CODE part of TS is 100% ECMAscript, and only annotations, which are not code, are added.

The initial Babel transpiler for TS => JS, and still the most part of the current one, simply removes annotations.

It is recommended not to use the few parts that are actual code and not standard JS. They are certainly not needed any more since ES6.

People may get confused because the type syntax itself is almost like a programming language, with conditions and all. But none of that ends up as code, it's not used at runtime.

One of the IMHO worst design decisions of TS was to bundle type checking and transpiling into one tool. That caused sooo many misunderstandings and confusion.

I think the point here is that all the TS tooling works with JSDoc without any friction. As long as you don't look into the file, from the tooling perspective, a .ts file and a .js file with proper JSDoc annotations are practically the same.