Battle tested and tooling really aren't compelling arguments anymore, Java is very middle of the pack in both regards. Go is running as the basis of the next generation infrastructure in Kubernetes, Prometheus, Docker, Terraform... Elixir has revived Erlang, which now has great tooling in mix and is well known for being highly reliable. Go, Javascript, and Rust all have real package managers (even Go with mod) that are bundled with the language and come with auto formatters, vetting tools, etc.
Also, funcitonal programming is a style of programming, not a collection of features. Just because you have a map and sort method and a hacked in lambda syntax doesn't make Java anything less than OO. Multi-Paradigm usually means one paradigm with a bunch of extra crap in there to make bike shedding easier.
