Personally, I started out in Scala as a 'casual' user using it as better Java/Kotlin. But, I have certainly seen myself gradually gravitate towards Haskell-inspired style. For many like me (with more exposure to OOP than FP in early career), it is a pedagogical device into FP. With regards to the future of Scala, particularly tooling, Scala may still be able to retain its 'casual' users with its recent focus on tooling : http://scala-lang.org/blog/2018/02/14/tooling.html