No screaming red banner, but each bucket does indeed get marked with large orange rectangle that reads “Public”. It’s easily noticeable.
In my limited experience, a lot of the open buckets problem comes from the fact that access to * is the path of least resistance vs a proper IAM and bucket config.
When feature work is on the line ain’t nobody got time for that :/
A lot of devs likely using aws in this manner are also not likely using the web interface an instead operating from cli pipelines where it’s easy to miss
