Actually, no, we have used it for a decade and continue to do so, because it is a reasonably clean and performant UI framework that gives us great control and pretty decent platform-native look and feel.
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.
And it looks like it was written in Java. Compare against any serious iOS app, for example.
I've been writing UI code for years, including in Java, .NET, Android/iOS, web, etc, so I have a pretty decent clue about building complex apps in all of these frameworks. Java just isn't a modern environment, and by being cross-platform you end up with an ugly lower common denominator that doesn't have useful APIs for non-trivial designs. iOS is probably the best framework/api out there and even that has many issues (luckily obj-c's categories help you fill in the holes).