On Plasma, I have it set up so I have all title bars hidden and I use custom keybinds to close, minimize and maximize windows, which saves screen space and reduces clutter. On GNOME you cannot minimize windows at all if I remember correctly.
I have virtual desktops disabled and only use one desktop to manage all of my windows, while GNOME fundamentally works around using multiple virtual desktops as far as I know.
GNOME doesn't have a system tray, which I find essential. For example, I can see just by looking if Discord has an unread notification. Or I can close OBS to the system tray without quiting the application, which reduces visual clutter. I know you can add this with an extension, but I'm just referring to vanilla GNOME.
I often use KRunner to temporarily write something while still seeing the contents of my screen, while GNOME's equivalent is full screen I believe.
I'm sure there are many other ways, but these are the ones I can quickly think of.