Kubernetes needs regular updates, just as everything else (unless you carefully freeze your environment and somehow manage the vulnerability risks) and that requires manual work.
ECS+Fargate however does not. If you are a small team managing the entire stack, you need to factor this into accounts. For example EKS forces you to upgrade the cluster to keep in the main kubernetes release cycle, albeit you can delay it somewhat.
I personally run k8s at home and another two at work and I recommend our teams to use ECS+Fargate+ALB if it is enough for them.
ECS+Fargate however does not. If you are a small team managing the entire stack, you need to factor this into accounts. For example EKS forces you to upgrade the cluster to keep in the main kubernetes release cycle, albeit you can delay it somewhat.
I personally run k8s at home and another two at work and I recommend our teams to use ECS+Fargate+ALB if it is enough for them.