What if instead of a dangling dns record, its 15 large EC2 instances?
Yes, you can come up with examples of trivial dangling resources, but it's just as easy for me to come up with non-trivial examples of dangling resources.
The number of articles I've read about someone who left a non-trivial number of resources running unused in AWS and were later surprised by a large bill would seem to be a counterexample to that point.
You should care. This opens you up to subdomain takeovers, which have real security implications.
https://developer.mozilla.org/en-US/docs/Web/Security/Subdom...
There’s also a risk that your legacy environments only work because some dangling resource wasn’t cleaned up, and a new clone of the environment will fail.
If you do this, or in fact anything with Ansible, be REAL careful about double-checking what your tags actually match before committing. Since it doesn't track state, anything in your cloud environment is fair game.
I was not careful once, and that was a bad week for me.