I've had a half rack in my home for many years -- if it's half empty, half powered off, and half full of low powered stuff, then it's not going to consumer a lot of power. (e.g. 'only' a few hundred watts) But 20u of 1u virtualization servers filled up -- or a single Nvidia DGX -- would easily overwhelm a normal home electrical system. The kind of workloads in datacenters are not people homelabbing for fun, but people running production workloads.