Qt (C++ + QML, python + QML or even C++ + QtWidgets) is well suited for desktop application development. You can easily stay with the open source licence of Qt. The Qt website is not really clear about this and they will push you to go for a commercial licence.

Electron (+ any web front-end UI framework, like React) will also do the job.

You can also check for Java Swing or Java Jetpack Compose.