Now it's possible to use whatever username you want for your system. The
default value of "user" is good if you're concerned about information
disclosure attacks through things like the username being visible in
logs or other output.
This makes it possible to define specializations that are technically
modules without having them placed in the modules directory. This is
mainly useful to separate core Hyprland logic from desktop environment
logic.
This makes it possible to boot into either Hyprland (the default) or
GNOME. Having separate configurations implemented in combination with
home-manager and impermanence guarantees that desktop environments don't
conflict withe each other, so this could also be used to implement a
Plasma specialization in the future.