It’s about the certainty to have what you want, where you want it, reliably. I run NixOS with Impermanence, which means I reset my root partion on every boot, and have what state I need specifically opt-in. And I run a shared config over multiple devices (home PC and Laptop), so installing something on one also installs it on the other, next time I rebuild. It certainly takes time getting used to, but I’ve been really enjoying it so far