> Traditional hosting still, to some extend, struggle to provide the API, on demand, drive requirements for modern developers, who expect to be able stand up a bunch of virtual machines in a minute or so, especially if you also want a new private network, maybe some IPs and storage pools.

If you don't like vSphere (who does?) you can do all that in Proxmox.

Proxmox isn't quite there yet for scalibility and hyperconverged but it is getting there really fast. It's more of a competitor to Microsoft HyperV HCI.