So it's 3.5 years old, and the CF was availabile this May. And it is a very widely used feature among many organizations.

If you want to use a new resource and feature, %90 likely it is an issue. There was even a public project to track them. https://github.com/cfntools/cloudformation-gaps/projects/1

You want to have an IAM role, but you can not tag it with Cloudformation. These minor frustrations quickly add up. And see what you need to do to add a custom resource: https://shouldroforion.medium.com/aws-cloudformation-doesnt-...