It's been around for 7 years and is maintained by two people as opposed to a publicly traded corporation (Qt) with hundreds of employees. It has already turned out.
There is no alternative to Qt. It is the best in its class.
But you don't need it. You don't need Electron either. Just build a .NET application for Windows, a SwiftUI one for Mac, and a ncurses one for Linux. They can all share the same business logic code (if it has any), either via C ABI, IPC, or RPC. Your application will always be at the bleeding edge with the latest security patches and accessibility this way, as opposed to waiting for the next Qt/Electron release which is guaranteed to be later than the OS bugfix. Imagine if desktop OSes release, in addition to dark mode, a pink mode. Do you want your application to stand out as the ugly duckling?