I've been trying to figure this out as well. The simple answer is that there is no consensus and no obviously right solution.

My constraints were:

- I'm not starting a desktop application project in C++ today.

- I don't want to do the heavy lifting for complicated widgets myself.

- I want to have the performance of compiled code without concurrency limitations (so no Python or Ruby).

- I want at least a reasonable facsimile of native look'n'feel on the three major desktop platforms.

- I want accessibility as at least an option.

If I don't want to buy dev tools like LispWorks or Delphi, then I'm left looking at Java + Swing or a backend in Java or .NET and a web frontend.

Then I look at Dolphin Smalltalk or Corman Lisp which are now open source on Windows, and they're phenomenal development environments that target Win32 directly instead of the layers added above it. macOS has excellent dev tools for just macOS. On Linux, GNOME and KDE both provide excellent environments. And I wonder if I should just forget about it and pick a platform.