On Windows, it's not even obvious what native is any more, even Microsoft just uses Web views. Mac is a bit better, but there are still 4 UI libraries to choose from (AppKit, UIKit through Catalyst, native SwiftUI and Catalyst SwiftUI).
I'm personally a fan of AppKit and Win32, but those are "dated" apparently.
Web is only native on ChromeOS and WebOS, because they don't have anything else as UI technology.
For Windows, "native" would be the classic Win32 UI "common control" elements from "Comctl32.dll"[0] that is directly used by older GUI frameworks such as Windows Forms. Those map to classic Win32 API CreateWindow(L"BUTTON", ...). In contrast, the newer frameworks of WPF and Xamarin Forms and Qt Quick "paints controls on a canvas" which are not "native" and makes every app UI look different instead of standardized "look & feel" of common controls.
But others include custom-canvas painting UI objects as "native" -- as long as it's not Electron.
[0] https://learn.microsoft.com/en-us/windows/win32/controls/com...
As far as I can tell, Qt Quick doesn't have anything like the same set of polished widgets that integrate nicely into the target platform. It's been this way for years, they just don't seem interested in implementing them.
GTK and KDE controls are native to GTK and KDE.
