There’s another issue which is system requirements. Qubes is extremely heavy. Though if a company needs such high security that they decide to use Qubes, they probably have more than enough budget for it (talking about cybersec, corporate espionage firms and illicit businesses). If it’s a more regular company, good luck teaching your employees.

Plasma probably seems a lot more familiar to people who are used to Windows, which I imagine was a consideration.

Cinnamon.

I have questions about KDE as the desktop choice. It is the leading DE in terms of adding new features and Wayland development but it’s quite unstable compared to something like GNOME or Cinnamon.

All extensions are disabled. I use the adw-gtk3 theme for GTK3 apps but I’m not talking about those (though the latest version of the theme also has smaller buttons that means the GTK devs probably have indeed changed the size of the buttons).

On the screenshot there is a GTK4 app that hasn’t been updated to the newest libadwaita version (Pipeline) on the left, and on the right there is a default GNOME app that has been updated (Console).

No I don’t use any scaling. Though I never checked if the update turned it on automatically.

Let the kernel do kernel job, chief. It aint a kernel no more if it does apps job.