Babel is a commonly used plug-in Webpack though. So I am guessing all projects that used Babel/Webpack got TypeScript support for free. It’s a TIL for me, definitely going to have to look into this. Sounds exciting.
A way to think about it is to consider TypeScript to be a linter, like ESlint - but one that you can help by annotating your code with e.g. the types of values you expect it to get passed. Babel can now strip those annotations before it transpiles your code, but you still need TypeScript to do the actual "linting". See https://vincenttunru.com/TypeScript-vs-Javascript
If you set the build target to ES5 you can still use modern features like async/await and it will rewrite them using a regenerator function that runs on older platforms.
Like most metaphors, it's not a one-on-one match.