> I'm amazed so many people pay the huge premium to get "instant scalability",
For personal use, the interesting part about cloud isn't the scaling up—it's the ability to scale down rapidly to (near) zero costs. I have a couple of GPU instances on AWS that I only use sporadically at spot-prices; when turned off, I'm only paying for the EBS storage.
If I were to rent servers from Hetzner (which I have done it the past for longer running things), it would cost me €40-80 a month, vs €10 a month.
(There's other minor niceties from cloud as well, for example: I also have a lambda in my account that when any instance starts, it checks for a DnsName tag, and configures a appropriate A records pointing toward that instance's new IP address)