I counted LISP out because unless you're using Clojure, I know for sure you're not going to be able to beat anything else for web-app development. LISP for web-app probably works in the 90's for PG but we're in 2015 where libraries, frameworks, and tools for these other languages are just far too advanced and more productive than writing macros... sorry mate.
Anyway, back to Java over Ruby/Python.
Take a few examples:
At the Microservice area, Java seems to shine over other languages/platforms. JAX-RS feels more complete than Sinatra or whatever Django plugins that the Python community use. See a quick example of JAX-RS vs Sinatra somewhere in this blog post: (http://www.appneta.com/blog/microservice-service-oriented-ar...)
Maven can be huge and underwhelming (and ugly once in a while) but it's definitely more powerful than gems+bundler+rake and whatever Python adopts these days. Maven has been around for a while so most Java DEVs don't have to pick up tools as Python DEVs have to do quite often. But again, there are trade-offs: Maven XML is definitely uglier than Bundler or requirements.txt or package.json.
Let me ask one thing: in platform other than Java, do you use declarative transaction? My guess is "No". Which means you have to know when to open and close a transaction (and potentially join an existing one if the library isn't smart enough). Java Spring/EJB provides annotation based transaction.
I'm not suggesting that Java is better than other languages, but there are advantages of choosing Java.
And, of course, at least they won't have do a rewrite when it becomes apparent that they have to scale big time.
Python is laughable. One word; GIL. Nuf said.
Java, and so Java EE is considerably faster than Python, each and every benchmark out there proves this. Often it's up to a hundred times faster.
Java has a much richer ecosystem than Python and even more so than Ruby. Java projects are also much easier to maintain and much easier to scale.
Enough backing? It's just the start of why Java EE is the better tool ;)