I agree with you that our industry should spend more time training frontend engineers. Frontend is often treated as an afterthought, which ends up being very costly in the long run.

That being said, the addition of types was definitely not us chasing a popular framework. Etsy adopts tech really, really slowly. We had a pretty specific set of problems that types had traditionally solved in many other areas of the stack, so we evaluated JavaScript type systems and decided on TypeScript.

I don’t really think the “types make bad code, functional programming makes good code” argument here is made in good faith — there are good and bad codebase using any paradigm you can think of. Give TS a try, or at least let me answer some of your specific concerns about it.