This is because I have to factor all the costs. This includes electricity, maintenance, incident response, networking, renting the cage, vendored software for backups, threat detection, fire suppression, equipment upgrades, licensing, alerting, and it goes on and on and on...
I'd challenge you to break down the full cost of owning a server as you see it. I bet you will miss 75% of the actual costs involved. I promise short of seizing a colo like its Nakatomi Plaza and running it at gunpoint you will never in a million years come close to the total ownership cost of cloud instance. You can't compete with the economies of scale and the caliber of the engineering.