Having worked with Erlang for few years. I still don't understand the new hype behind it.
Ok, the Beam VM have a lot of good ideas. But I think that API of OTP and the language itself do not help to make concise and maintainable code.
And you're pretty much on your own about tooling. I really think that even if you can achieve good performance/scalability in theory, in practice your team become less productive.
I actually did with my company and anyway it was a bad decision.
JavaFX and swing customization is really not easy and not well documented. JavaFX uses custom XML which make no sense to be honest when you want to do nice design.
And it requires custom CSS too.
Additionally, their design are bad(I mean their Java API).
We spend a whole year making an app with it, at the end we decided move away from it, like the rest of the java community if fact that do not really support desktop applications anymore.
Vue is good for simple things. But it do not shines for complex apps and sometime makes it even harder than it should be.
React can appears complicated when beginning, but it pays off on complex apps.