Hello,
Yes, As you have pointed it out correctly it is not recommended to use gsutil for Cloud Storage as mentioned in the public document. Since you are facing issues with gcloud tags, I suggest you use gsutil as a workaround only.
You may also refer to this StackOverflow for comparison b/w gcloud and gsutil. Since gcloud is the recommended command, And as it is not working as intended I suggest once again to raise a public issue tracker.