But a PC like what you’re suggesting would result in a much higher energy bill compared to a Pi if you leave it on 24/7 to use as a server.
Those Intel N100 machines sip power. Supposedly with some tweaking, people have gotten them down to idle at ~2watts.
I've got a i5-7500T box running as a Proxmox Backup Server, and it idles at 6-7W. It runs at near idle most of the time (it's just running PBS and a few network services), so I'm not expecting it to cause much difference to my power bills. Even under full load, it only draws ~30W, so it's not _that_ much power.