@atpfm @siracusa @marcoarment @caseyliss

To clarify how Hide My Email works, you’re actually only supposed to receive emails from designated domains as prescribed by the developer. Refer to the support page:
https://support.apple.com/en-sa/105078

This will therefore allow you to keep using the same alias email address during data breaches where presumably non-designated domains will try to spam/scam you.

However, unintended consequences of this is that sometimes you do need legitimate emails from non-designated domains. I personally bave a rather frustrating experience. I used Qeeq to rent a car and I purchased the insurance add-on on Qeeq but the insurance was offered by a third party vendor. I had an accident and there was some lost communication from the insurance company during the claim process whose emails never got through. Unfortunately, there was no way to find them in junk or anywhere. Just vanished out of existence.