As a programming language polyglot, currently using Java for backend services, one of the biggest reasons to use Java is due to the ecosystem. Hardened libraries for web frameworks and everything else under the sun means you have confidence in the language. You have millions of instances running in the wild so detection of issues are found and resolved quickly, corporations backing security audits and a lot of funding to make really good libraries.

I hate the language itself and would never choose it as a language for a hobby project, but i completely understand why Java exists and thrives.