[tcard]

Sure, but plenty of type systems are Turing complete. What makes this demo impressive is the (unique?) feature of string literal types and template literal types, which lets you operate on text (like, actual text, with no weird type-level encodings).

[Quekid5]

Well, certainly string literal types have been around in GHC Haskell for quite a while (7.10.x). They've also been a thing in Scala 2.12.x although the 'implementation' was some sort of weird type checker 'hack'. I believe Scala 3 supports them natively.

I can't speak to the ergonomics of actually implementing anything which uses them internally since I've never really had much use for them outside using the surface-level API of a couple of libraries.