No, while this is sometimes used for private properties/methods, TypeScript never used it. TypeScript's private properties/methods are just compile-time errors, they're still public in the generated code.
According to this[1] exchange on Stack Overflow, the IIFE is used by TypeScript because of other scoping issues (specifically protecting class properties before instantiation and defining interfaces).
[0] https://yakovfain.com/2015/06/30/the-private-in-typescript-i...
[1] https://stackoverflow.com/questions/56086411/why-does-typesc...