[xylophile]

> But you would still need a boatload of a hundred unique VMS

No, you would have a boatload of generic worker VMs that could all be spun up as needed (autoscaled) from a common base image and deleted without any need to preserve state. Effectively, you're managing one VM image, which can be rolled out across your entire fleet very quickly and with zero downtime / disruption. This is even less disruption than with k8s because FAAS design is fundamentally short-lived processes, resulting in more automation (less work) for your SRE / VM team.

[oxfordmale]

As far as I am aware there is no easy to set up open source FAAS framework. At least with Kubernetes there are a million and one tutorials, and there is a large support community.