Unless I'm misunderstanding something, I'd expect modules/index.js to re-export ../tslib.es6.js instead of ../tslib.js.

https://github.com/microsoft/tslib/blob/master/modules/index.js#L1

I'm basing my statement on the understanding that exports['.']['import'] should point to some "modern" code:

https://github.com/microsoft/tslib/blob/master/package.json#L29-L34

(The reason I'm opening this issue is that I'm facing some problem in combination with Vite which is based on ESM.)