"a much better concurrency model"
If your program is CPU-bound, where real threads are king, then Erlang is a pretty poor solution. Because you cannot have real threads in Erlang, even if you wanted to. Number crunching or string processing are not its forte.
Also, most enterprise software does not really benefit from green threads anyway, because the scale they are running on easily handles blocking JDBC and http request calls. Not all companies are google or want to run a telephone switch that handles >million concurrent calls...
And finally, if you go Erlang, you get actors, whether you like them or not. You cannot have CSPs, for example, which in many ways are superior to actors. You don't get to choose your concurrency model, it is chosen for you. If your use-case suits this model, great. If not... not so much.