Yeah that's basically it for me. I have a collection of dev boards, old hardware and stuff other people were tossing out set up for a variety of purposes (Kubernetes clusters, two build farms, network boot, etc.). None of it is because I feel I "need" any of that for self hosting. In practice two old desktops with a bunch of drives would be perfectly capable of providing everything I need including redundancy. I have all that stuff because I'm learning and experimenting.