I just don't see it. Given the nature of the services they offer it's just too risky not to use as much managed stuff with SLAs as possible. k8s alone is a very complicated control plane + a freaking database that is hard to keep happy if it's not completely static. In a prior life I went very deep on k8s, including self managing clusters and it's just too fragile, I literally had to contribute patches to etcd and I'm not a db engineer. I kept reading the post and seeing future failure point after future failure point.
The other aspect is there doesn't seem to be an honest assessment of the tradeoffs. It's all peaches and cream, no downsides, no tradeoffs, no risk assessment etc.