Can an iCloud Alias be Deleted and Reused on a NEW iCloud Account

Note this Sept. 2021 postwhich was Recommended by Apple --> "It appears you cannot add an iCloud alias as your Apple ID, you can only use the iCloud email address that is the basis for your iCloud mail account which is the old name. If you do not want that as your Apple ID then you need to set up an external email account or you would have to create a new Apple Account." - How to change Apple ID? - Apple Community

And:

Create an email address in iCloud Mail - Create a primary email address for iCloud Mail - Apple Support - "Note: You can’t delete or turn off a primary iCloud Mail address. You can’t use an alias to create a separate Apple ID, and an email alias can’t be converted to a primary iCloud Mail address."

I speak without authority here but my thought would be "no". If that were possible then if you had been using the alias xyz@icloud.com, then removed it, and another person was able to create an account xyz@icloud.com then there would be the risk that the new user might receive messages being intended for you.

You can try asking Apple:

Contact Apple. Click here --> Choose your country or region - Official Apple Support Select your country, then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.

or:

Contact Apple for support and service --> "See a list of Apple phone numbers around the world."

Click here --> Contact Apple for support and service - Apple Support