The main options.
WHAT THE ESTABLISHED COMMERCIAL PLATFORM PROVIDES
Mature management Live migration and automated placement Extensive ecosystem Strong support
What it costs: substantial licensing, which has changed significantly.
WHAT THE MICROSOFT PLATFORM PROVIDES
Integration with Windows environments Included with the server operating system Familiar management for Windows administrators
WHAT THE LINUX KERNEL HYPERVISOR PROVIDES
Virtualisation built into the kernel No licensing cost The foundation of most cloud platforms
WHAT PROXMOX PROVIDES
A management platform built on that hypervisor and containers Clustering, replication and backup included A web interface No licensing cost, with optional support subscription
WHY IT SUITS SMALLER PROVIDERS
It provides most of what commercial platforms do, without the licensing.
WHAT TO CHOOSE ON
Existing skills Licensing cost Required features Support expectations
WHAT MATTERS MORE THAN THE PLATFORM
How it is operated: backups, monitoring, and tested recovery.
WHAT TO AVOID
Choosing on feature lists rather than what you will use.