Scala moved the needle five years ago and made java better among other languages. Using scala helped me grow as an engineer. in my view, it has no place in an enterprise. I require a mature environment that favors consistency. It boils down to reducing complexity. I can barely handle the complexity growth due to the demands of the business, whether it be software engineering or people and these reasons do not justify scalas pluses. Ymmv.
I think scala can absolutely account for that complexity, like it is not a one-way street. It can scale both up and down on expressivity. But I agree that often times it is not used that way.
I wouldn't say spark is terrible, but it is a sort of a "reverse bicycle". If you put a spark codebase down for a week or two and pick it back up, it feels like you're learning everything all over again.