The phrase "Each platform’s native UI toolkit" suggests that each platform has one specific native toolkit. That misconception is what I was addressing. To put

The phrase "Each platform’s native UI toolkit" suggests that each platform has one specific native toolkit. That misconception is what I was addressing. To put it in practical context, apps built with Gtk generally stand out like sore thumbs on Qt-based desktops like KDE Plasma, both in the way they look and in the way their widgets respond to input. This rather undermines the app's claim "to deliver the best experience" with its choice of UI toolkit. But if you like, go ahead and believe that I'm wrong instead of trying to understand.