> There's been some times where I needed python for systems that weren't so lax about what I was able to install, and python was already there.
FWIW if a system has Java and Maven installed (i.e. any machine set up for Java) then you can use Scala there (indeed I'd say that's a much nicer way to use it than installing it at the system level). Unfortunately Scala tooling isn't really set up for starting quickly if you're not familiar with it, even though it's actually a pretty decent language for one-off scripts.
There's been some times where I needed python for systems that weren't so lax about what I was able to install, and python was already there. Other than that, I've never really come across a reason disqualifying scala, barring know-how and time to learn it.