It's true that some features of Scala have made it to Java, but I am not sure the gap between the two languages has shrunk much. For example while Java has added first-class functions and closures, it is still clumsy to attempt any serious functional programming approach with Java; Scala's type system is still way ahead; Scala compile to the JVM, JavaScript, and now native via LLVM.
> having libs tied to what version of the compiler you're using
It's never been that. However libraries used to be tied to the major version of Scala (for example 2.11, 2.12, 2.13) as major versions were not binary-compatible with each other.
Scala 3 addresses this thanks to the TASTY format which creates a strong foundation for binary compatibility. [1] You can use Scala 3 libraries with Scala 2.13 and, more importantly, Scala 2.13 libraries with Scala 3.
unless you like ridiculously long compilation times and having libs tied to what version of the compiler you're using (serious WTF)