On the other hand, KDE is the most configurable DE I've ever seen. I've never looked too much at its defaults because I usually switch to KDE in my "let's customize everything" moments (and get back from it in my "let's learn to live with defaults" ones).
Being able to bind almost everything (including running custom scripts) to a keyboard shortcut, having tons of desktop options you can force by matching window or app properties, using special attributes or regexps, all of that screams "don't use default and customize me" to me, which is where KDE really shines, IMO.
I agree. It's almost customizable to the extent I'd want. Except that several things don't work because they're either not under KDE's control (shortcuts for Firefox, Chrome, Gtk apps, etc.) or its flexibility is subverted by the layering of its concept of Global Shortcuts, Application Shortcuts, and where both of those things slot into event handling along side Xorg.
Being able to bind almost everything (including running custom scripts) to a keyboard shortcut, having tons of desktop options you can force by matching window or app properties, using special attributes or regexps, all of that screams "don't use default and customize me" to me, which is where KDE really shines, IMO.