Some things like conditional types and string template literal types start to get way out into abstract type land that is certainly more advanced than C#'s type

Some things like conditional types and string template literal types start to get way out into abstract type land that is certainly more advanced than C#'s type system. Typescript is inching closer and closer to the Haskell-ish land of turing complete type systems where the type system itself is nearly it's own meta-programming language with each version. (A recent example was the "SQL engine" written using string template literal types to type safe "query" an in-memory database. That's quite more advanced than anything C# is capable of, albeit a strange hack and unlikely to be specifically something useful in production anytime soon, though still built out of things that make Typescript useful to some JS projects.)