It is largely a mature language and the inherent flexibility of the language means that a lot of things that require new language level constructs in other lang

It is largely a mature language and the inherent flexibility of the language means that a lot of things that require new language level constructs in other languages like Java aren't needed here. The interesting stuff is happening in the runtimes (See TruffleRuby https://github.com/graalvm/truffleruby https://github.com/graalvm/truffleruby )