I ran renderapp in ECS before I ran it in k8s.

The deployment files / structure were mostly equivalent with the main differences being I can't shell into ECS and I lose kubectl in favour of looking at the AWS GUI ( which for me is a loss, for others maybe not ).

The main difference is k8s has a lot of optionality, and folks get analysis paralysis with all the potential there. You quickly hit this in k8s when you have to actually need the addon to get cloudwatch logs.

This is also where k8s has sharp edges. Since amazon takes care of the rest of the infrastructure for you in ECS, you don't really need to worry about contention and starving node resources resulting in killing your logging daemon, which you could technically do in k8s.

However, you'll note that this is a vendor choice. EKS Auto Mode does away with most of the addons you need to run yourself, simplifying k8s, moving it significantly closer to a vendor supported solution.