Yes, and I am aware of the histories, we just want (and need) something more now. Typescript still seems well positioned for this. Not many reasons you cannot fix this with a compiler flag (which is default off).
You would have to change the entire type system to make it C# like. TypeScript makes radically different assumptions about static typing than C# does. It also would be difficult to come up with a run-time type representation that was even sensical (due to unsoundness), let alone efficient. It isn't just a compiler flag that you want, its an entirely new language.
