There are two issues - one is that the permission model of Linux may not be suitable for modern workloads, but the second is that Linux is a huge, constantly-mo

There are two issues - one is that the permission model of Linux may not be suitable for modern workloads, but the second is that Linux is a huge, constantly-moving beast written in a memory-unsafe language and has regular privilege escalation exploits. Addressing the former still won’t address the latter. Hypervisor-based security seems to be the least worst way to deal with this problem currently, and indeed appears to be a successful defense given cloud providers’ bottom-lines.