I'm aware of that initial support, I've been followed that since they added the experemental flag.
As far as I know, it requires some non-standard usages in TS code, like adding the .ts extension to your imports at the top of your TypeScript files. It doesn't support .tsx files or any TypeScript feature that requires more than type striping. The initial support is appreciated, but it's not on part with Deno or Bun yet.
TL;DR you will still need to work on adding proper TypeScript support anyway, compared to Bun.