[EKS] [DNS]: why can't we use route53 in place of coredns.

**Tell us about your request**
What do you want us to build?
Can we replace coredns with route53 (cloudmap) completely?

**Which service(s) is this request for?**
EKS

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
Firstly coredns is an additional dependency for kubernetes.
Second service discovery requires additional tooling. Usually to make an internal service accessible I have to create a headless service so that external-dsn creates an A record with all the pod-ips. Since kubernetes service discovery is already using round-robin dns internally, I see why can't we use the same for exposing microservices internally (or even externally through public-ip).
With coredns replaces by route53, all the above steps I am assuming are out of box. Even a kubernetes svc is completely routable from anywhere within vpc.

**Are you currently working around this issue?**
External-dns

**Additional context**
While talking to community I couldn't understand how dns resolution from route53 is insecure in comparison to dns resolution from coredns. We have coredns plugins to replicate all entries from route53 to coredns. Wondering if its related to this https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/domain-configure-dnssec.html

The request concerns replacing CoreDNS with Route 53 or Cloud Map for EKS service discovery. Start by reviewing the stated Kubernetes, VPC, headless-service, external-dns, and DNSSEC questions and the linked Route 53 DNSSEC documentation. No repository files or tests are identified; done would require a decided, scoped feasibility or implementation plan.

Written by the indexing model from the issue text.