[jeroenhd]

Qt on Windows looks pretty out of place. Qt copied Windows Vista pretty accurately, but I haven't seen any fluent design yet. The Vista style also looks a little off now that Microsoft has tweaked the native controls in Windows 11.

KDE applications look out of place in Gnome. Some Gnome distros pack GTK-like themes for Qt applications, but Dolphin looks like ass on Gnome. Depending on your theme/night mode settings, it's also broken (black labels on dark grey backgrounds broken). Gnome apps may look out of place elsewhere, but at least they're functional.

I, too, can't deal with different behaviour, but KDE is no better than Gnome when it comes to integration. The core application UI design approaches differ, so I doubt good UI integration can even be done; cross platform applications would need complete UI overhauls for every platform they target, ruining the whole point of cross platform UI toolkits.

Thankfully, Linux applications using XDG portals will invoke native controls for features like file pickers, limiting the damage both ways. I expect something similar to happen on macOS and Windows.