You’d be swapping an open-source vendor independent API for a cloud-specific vendor locked one. And paying more for the “privilege”

I mean that's the sales pitch but it's really not vendor independent in practice. We have a mountain of EKS specific code. It would be easier for me to migrate our apps that use ASGs than to migrate our charts. AWS's API isn't actually all that special, they're just modeling the datacenter in code. Anywhere you migrate to will have all the same primitives because the underlying infrastructure is basically the same.

EKS isn't any cheaper either from experience and in hindsight of course it isn't, it's backed by the same things you would deploy without EKS just with another layer. The dream of gains from "OS overhead" and efficient tight-packed pod scheduling doesn't match the reality that our VMs are right-sized for our workloads already and aren't sitting idle. You can't squeeze that much water from the stone even in theory and in practice k8s comes with its own overhead.