To me, it sounds like your company went through a complex re-architecturing exercise at the same time you moved to Kubernetes, and your problems have more to do with your (probably flawed) migration strategy than the tool.

Lifting and shifting an "EC2 + ASG" set-up to Kubernetes is a straightforward process unless your app is doing something very non-standard. It maps to a Deployment in most cases.

The fact that you even implemented an operator (a very advanced use-case in Kubernetes) strongly suggests to me that you're doing way more than just lifting and shifting your existing set-up. Is it a surprise then that you're seeing so much more complexity?