You're unfortunately right. Every Scala codebase I have seen recently is essentially legacy. New services are not built with it anymore. Other than blaming SBT and the Haskel fans I'm not aware of a technical justification. But the industry/community has shifted since 2015-2018.

The only rare exceptions I heard of were strict FP shops who share nothing with common JVM-based development. You could have a few years of full-time Scala experience with Akka and Spark and they won't even screen you.

In the year of our Lord 2024 the question is if you want to bet on Java21+ catching up with Kotlin or go with Kotlin from day one. The choice is less obvious nowadays. I'd go with a modern language, actual job market sides with Java still. At least on the backend in the Bay Area.

As a side note, I cannot imagine a competent JVM-based developer not familiar with either Kotlin or Scala by now. In a typical Java shop half of the team is dying to switch to one of them in my experience.