Why isn't there a way to make near-native desktop UIs that's similar in ease to browser and electron UIs?
It depends on just how "cross-platform" you want to make it. If you came up with another standards-based UI framework that had the same cross-platform penetration of web browsers, then you'll have effectively reinvented the browser. For everything else, you can basically pick a maximum of two: cross-platform, native, and easy.
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