It seems to me that companies that choose non-JVM languages (with the exception of .NET) for important server-side projects are those that have always opted for the flavor-of-the-month. Most of those using Go/Elixir/OCaml/Haskell today, are those that used PHP, Ruby, Python or Node yesterday, and are likely to pick something new tomorrow. All of these choices have deep, fundamental and serious problems -- both technical and environmental -- that are unlikely to ever be solved, but are all solved on the JVM. Those problems are sometimes obscured by the novelty and promise of the shiny alternative, and take a while to be felt among those who always opt for the new thing, but they are invariably discovered later on, and by that time something newer comes along, whose problems are yet unapparent. The problems are there because unlike Java and the JVM (and Fortran, COBOL, C and Rust), those platforms were not developed after careful consideration of the industry's needs (Erlang/Elixir is a different story, and, indeed its
fundamental problems are more environmental than technical).
In addition, in smaller/less-critical projects, Java was an accidental leader in a short period of time where the competition disappeared and Java itself was novel, but it was never "supposed" to be there to begin with. VB and Delphi were very popular choices early on. I'd estimate that even when Java was the shiny new thing, VB, Delphi and other rapid-development languages had a larger share of the market than Go, Node, Ruby, Python, Haskell and OCaml combined today. And frankly, I don't see companies developing en masse large-scale applications in C++14. Unless you have very specific needs, there's just no reason to go there and pay a higher development cost, and if you do have those needs, you're probably already there.
In large corporations (including trendy ones, like Google, Amazon, Netflix, Twitter and many more, let alone more conservative ones) the JVM still reigns supreme, with competition lagging far, far behind. I'm not saying it won't eat into the JVM's market share -- although they're mostly cannibalizing one another -- but I don't see any potential leader in the pack. It's possible that there won't be one, with many sharing the cake.
So I think that (again, with the notable exception of .NET) the non-JVM market is composed of novelty-seeking organizations and a share that wasn't Java's to begin with, but accidentally was for a short while (the two segments intersect).