1) It's not "cool" 2) It's still saddled with performance FUD, although people are finally realizing it's really fast 3) The ecosystem is huge 4) It isn't suitable for everything, e.g., it often just makes more sense to use something else for the front end (client-side) and use Java tools for infrastructure (search, messaging, etc.) 5) Java's "true" home is the enterprise, and it's pretty well-suited for that: it's well-known, ubiquitous, performant, and can interface to anything
You're looking at self-selected jobs, which skews your perception of what people are looking for. As a counter-example, I probably get 2-4x Java emails compared to other ecosystems combined. To be fair, most of those emails are for boring jobs, but a lot center around big data.
With the switch to client-side frameworks Java web apps are a dying breed outside of the enterprise, but the back-end API can be anything.