Deleted iCloud Rules Are Still Being Applied

Clarification:

This is an iCloud rules problem (server-side); not Apple Mail rules. It affects all devices.

Question:

I would like to know if others are still having this problem and if they found a solution other than deactivating/deleting the email address.

The Problem:

I deleted all my iCloud rules, but found that they were still being applied, even a month later. One rule funneled mail from an alias into a particular folder. When this alias was used by a malicious actor to sign me up for various joke of the day emails, I deleted the rule and the folder thinking it was somehow interfering with the spam rules. New emails from slightly different addresses kept arriving and the folder was re-created to house the joke emails. Apple Support confirmed the rule behavior and reported it to Engineering. The only solution I found was to deactivate the alias. Unfortunately, other rules were not as well-contained and required me to change emails for many websites and newsletters.

Comment:

I noted that this problem with iCloud rules was posted by another user over a year ago, and it is a shame that it has not yet been fixed.

Theory:

I suspect that this problem stems from a change in my Apple ID that occurred after the rules were created. It is possible the old Apple ID was not completely deleted.