I use KDE. My configuration for the title bar includes a “keep on top” buttons (it’s one of my favourite little Linux things, along with middle click paste, which of course GNOME also wants to remove). On the left side near the application icon. CSDs, which I sometimes use (e.g. Firefox) never include this.
I also can’t just access the KWin menu by right clicking, as I would on a normal window, I have to right click the icon on the taskbar (I do use the windows grouping in the taskbar, and that means even more clicks) or I need to use Alt+F3. Which is not too hard, but it means needing two hands for something that should need one.
So there are applications that manage to make CSDs so useful that the drawbacks become acceptable, but it’s honestly not too often.
And that’s absolutely your privilege to do, since you use KDE. Which is the point.
Some things i like to do in “keyboard heavy” mode, and for other things I want to be a one handed mouser.