Oh, I don't disagree, I just meant it can be as complex as you want it to be. Hardening is just a rabbit hole that can go on almost forever - it's never really final until you declare that enough is enough, typically there's always something more one can do, if they have time and capacity.

Also, out-of-box distributions those days can be said to be already "hardened" compared to what we had 15 years ago.