I challenge you to do anything that is first-class profession UI/UX experience in Java, and not want to tear your eyes out in the process. Try building something Aperture, Keynote, etc in Java. I don't know what you're building but my guess is it isn't 'beautiful' or innovative UI.
True, but how many of us programmers either want or need to do that?
Less than 1% I'll bet.
For the rest of us, Swing works just fine, and it's a whole lot better than some of the other UI toolkits out there.
Except basic interfaces can still be done with things like iOS. If you're going to take the time to build a UI framework, it shouldn't specialize in being craptaculuar.
I'd also venture to say a lot more than 1%. Modern world (finally) recognizes that design/experience are core to any product, enterprise or not. That's part of the reason there's a whole new breed of funded enterprise companies out there -- they're taking lessons from the web/apps and applying them to replace old-school solutions. [I'm personally hoping more people recognize this need for developer tools which typically are the worst offenders of all, particularly on the database side.]
Part of having a good framework is what allows apps/applications to excel -- it helps you raise your own bar because the tools are just so much better that nicer UI/UX can be had without being a nightmare in code. That's a win for everyone.