I'm not sure what you're trying to convey. Most/All? modern JavaScript engines compile JavaScript (including v8).

But you still have to actually run the code to find a lot of problems you can find in TS at "compile" time.

lolwat?

I think the parent is referring to JIT Compilation as a type of "compilation" as opposed to being interpreted. Of course the original post is tackling the type-safe aspect of compiling vs performance.