Is JetBrains Runtime worth considering for a Swing app?

JetBrains Runtime, usually called JBR, is worth a look if Wayland support matters to you. JetBrains also contributes to OpenJDK's Project Wakefield, which works on Wayland support.

Check the JBR release cadence against the Java versions you plan to target. The discussion raised its focus on long-term support releases as a possible drawback for apps that move to newer Java releases more often.

Keep the runtime and the UI framework decision separate. JetBrains applications have a lot of abstractions built on top of Swing. Switching to JBR alone won't give your application those layers.

JetBrains is also developing Jewel alongside its existing UI work. That may be worth watching, but it doesn't establish when or whether plain Swing would be phased out.

I'd start by checking how far ordinary Swing gets you before adding another dependency. If it covers the UI you need, JBR can still be evaluated separately for its runtime features. There isn't much reason to take on extra UI layers just because they're available.

If browser support is part of the decision, SnapKit is another option to investigate. It is based on Swing and includes features inspired by JavaFX. Check how well it fits your application rather than assuming an SWT conversion would be straightforward.