The wealth of things in the KDE settings are things people will likely never change or are things that can be tweaked but don't necessarily need to be. For example, let's look at GNOMEs settings app. It has menus and options for all the things that the average user needs (network settings, mouse and display options, etc.) but leaves out, for example, things that people need to change for specific workflows (like the option to have focus follow the mouse). A settings app should let the user set things needed for the functions of a computer to work properly while separating deeper level customization for those who want it.

I think emacs does a very good job at this. You can configure most of the settings people need to be productive in a text editor from the menu bar while leaving the extremely rich customization of emacs to the options menu and elisp config files