There is also a route of a fork. Adding generics doesn't look very hard to me.

This will only target a very small group of developers, who are comfortable with JVM, but not with Java or Scala. I don't see any money there.

JVM is a major drawback for any language. Many people don't even look at JVM languages.

I doubt it. I did Java for over a decade, but jumped at the opportunity to use Go with its statically compiled binaries. The JVM is great, but being tied to it is kind of a hassle. Being able to hand a small binary to someone and say "here, run this" with no worry about dependencies- it's a beautiful thing.