It looks mostly ok, but on Linux it doesn’t support smooth scrolling (even though this is supported by gtk). You also can’t use the meta key (windows key / cmd) as a modifier key for keyboard shortcuts. So I can’t configure intellij to use all the keyboard bindings I’m used to from macos. Again, this isn’t a problem with other gtk apps. It’s just (apparently) a platform limitation of whatever Java toolkit they’re using.

So in my experience it’s 95% of the way there. I certainly prefer it over Xcode, but it has issues that native apps don’t have.

First of all, up-to-date official packages are now published to Maven Central as part of the release process, so you can just add it as a dependency as easily as with any other library. Until recently you would have had to either fiddle around with Eclipse's alternative package management system, download it manually or use someone's unofficial Maven artifact. But that's now resolved.

Secondly, if you bundle a Java runtime customized with jlink (as is recommended these days), an SWT application is actually smaller than a Swing application. When you don't use Swing, you can exclude the entire "java.desktop" module, which is slightly larger than the SWT libraries.