But, even if you restrict it to 'x86 virtualization', the alternative for the current crop of 'enterprise' OS environments is ...server sprawl. I'm a big fan of discrete hw for some things, but it can be a hard sell for everything.
The primary alternative to full system VMs is containers (or jails, zones... whatever your OS might call them). You don't need to go server sprawl or VMs as the only two options.
But, even if you restrict it to 'x86 virtualization', the alternative for the current crop of 'enterprise' OS environments is ...server sprawl. I'm a big fan of discrete hw for some things, but it can be a hard sell for everything.