My company (a large-ish pension plan, ~10 dev teams, most applications are internal) was on AWS Beanstalk and switched to Kubernetes (EKS). Once we moved in and cleared the initial hurdles, the overall impression is that K8s is very pleasant to work with: solid, stable, fast, no bad surprises. Everything just works. We probably spend 0.1 FTE taking care of Kubernetes now. Definitely was worth the cost.

All AWS tech I've tried before (ECS, Beanstalk, plain EC2, Cloud Formation) is slower, has random quirks, and needs an extra layer of duct tape.