Java does have some unfortunate complexity, but I don't think it is in the same league.
Java also includes a library that is more extensive in some areas than the vanilla standard C++ one.
The JVM is also more robust to some types of programmer errors than any run time for C++ that I know of.
Most of what the code does is hidden behind ceremony.
Imagine Newtown writing out instructions on how to calculate gravity instead of just writing: F = G((m1 m2)/(r^2))
I really don't understand how a language that can't succinctly express calculus from 300 years ago would be regarded as suitable for complex code.
Most Java programmers don't care about expressing calculus. They care about expressing interactions between web services, sql, and applying rules as the data flows through their modules. Or between user interface elements and service requests. It's all about moving data around, working on that data when you've got it, and triggering actions.
As you point out when you have a reasonably complicated problem like applying functions java fails miserably and other languages are a much better choice.
So server-side Java lives in a niche and I would never suggest it for, say, anything client-side or basic web apps.
The runtimes aren't that much slower, and for I/O bound tasks, odds are Node is going to run just as fast with less application complexity.
No, in the real world, it's exactly the opposite. Nobody cares about writing a function because generally that's the simple part. Do it however you want. Deploying the system to take inputs and feed outputs, now that's the hard part. Where do those inputs come from? In what form? Are there security requirements to gather or push data? Do you store-and-forward or don't you? What protocol? Stateful or not stateful? Transactional or not transactional? The problems involved in "move these bits in this format on this machine to those bits in that form on that machine over there" are in fact so complex that you can't even prove it to be an NP-complete problem because the problem itself transcends algorithmic analysis. It is much more a social problem than a technical problem, but the social problem is so massive that any simple-minded technical approach will fail to address the scope of the issue and in every case I've ever seen, simply makes the problem worse.
Hell, Scala is one INSANELY complicated language. It's got about every feature under the sun. Java is simple and to the point...unless you really want to use spring or something of the sort.
Anyway, you've got a really contorted view of Java, and you are conflating some fundamental things.
And its not about complexity or features in a tool, its about how those features interplay with the base design of the tool.