The dot-d notation is there for applications/packages to affect a subsystem without messing with that subsystems’ own configuration settings. Debian makes good

The dot-d notation is there for applications/packages to affect a subsystem without messing with that subsystems’ own configuration settings. Debian makes good use of it but i found that it introduces a smaller problem of ordering (which of the app’s setting to apply firstly for that subsystem’s dot-d collections of apps’ settings. But such conflict of inter-app configuration settings is seemingly rare and often best done directly into such subsystem’s own main config settings.