I was and continue to be surprised how reliable even old servers are. I run a small homelab (Debian VMs on Proxmox; a Docker host, a jumpbox, a NAS running ZFS, etc.) on seven year old hardware, and all of my problems are self-imposed. If I leave everything alone, it just works.

As a counterpoint, though, my last place had a large Java app, split between colo'd metal and AWS. Seemed like the colo'd stuff failed more (bad RAM mostly, a few CPUs, and an occasional PSU). Entirely anecdotal.