I work in hosting. We mostly use Proxmox for our Hypervisors which is already a step up from “bare” KVM in regards to convenience/ease of use (especially for High availability scenarios and the like) We also run VMWare and while I don’t love the “locked down you gotta do it the VMWare way” nature it’s often so much easier and the HA is mich more convenient. Also it has proper functionality for custom resourcing/access/billing.