[jo909]

Once upon a time nobody seriously thought JavaScript would ever play any role outside of the browser, and even the role in the browser was small enough many people preferred to disable it.

Then we got a very fast JIT, and suddenly you could do reasonable compute heavy stuff very fast, and then it became viable to also write the server side in JS, because of programmer efficiency and library reuse and other reasons.

The "right tool for the job" can seriously change when tools improve and develop, and just because there already are other tools for the same job should not stop anybody from trying.

I can not think of a better example for that than JavaScript.