Interesting how nobody seems to have mentioned React Native here. Its Windows support is still rough round the edges in some situations (e.g. third-party library comparability) but the experience I’ve had so far using it to build a cross-platform app has been great. I’d imagine if you need to do more system-specific things e.g. the Windows task tray icon, you may still need to reach into the skeleton project and write some OS-specific code in C++, but the majority of the app I’m just writing in React, and there’s even a tailwind port for RN that worked out of the box. I also heard that Flutter upped their support for desktop a lot as well.
And by the way, I just realized that Windows 11 is going to support running Android apps https://blogs.windows.com/windows-insider/2021/10/20/introdu.... Of course it's not gonna suit every app (seems that OP requires a lot of performance in the app), but I'd imagine it would help ease development efforts a lot for a lot of apps that are not so demanding. Even if the phone layout will not be suitable, the tablet layout should be good enough in most use cases.
