Having written both Haskell and Scala professionally, I actually see Scala's dependence on the JVM as its biggest flaw.

If it weren't for the JVM Scala could make do without an Any type and without having to deal with null values. I hope that alternative runtimes like Scala Native will become more popular, since Scala could evolve away from its JVM roots then.

I'm also not a fan of JVM performance optimization, since there are too many knobs to turn, and the knobs often have (undocumented) side-effects on other knobs. This is a lot simpler with the Haskell runtime (in my experience) since you mainly need to tweak the GC settings there.

You really should never tweak anything in case of the JVM other than perhaps max heap size and rarely target pause time (for G1, so you can either prefer throughput or latency). Anything else you find online is likely already outdated and very specific for a given code. Instead just use a recent JDK and profile your code.

As for scala, missing the java ecosystem would pretty much decimate the language, no matter how cool it is.

I know others who share the same opinion as you, so I can relate.

That being said, the Any type would be there in any case - this is not JVM specific. "null" is, but I think it's not too much of a big deal with Java 3's Union-types, see: https://dotty.epfl.ch/docs/reference/other-new-features/expl...

The only problem is that if you now use native Java libraries, you'll be confronted with everything being explicitly nullable (no runtime error problems though). But that's a small price to pay for having access to this huge ecosystem.