Unless I'm misreading your question, doing the following will make the process easier for you:
Launch the App Store app on your iPhone
Tap on your account at the top right corner
Tap on Purchased
Now you should see a listing for all accounts in your family group
Tap on your wife's listing
At the top, below your wife's name, you'll see two buttons All and ...
This is an iCloud keychain prompt. In order to allow you to sign in to the Mac, you'll need to approve it. If you only have one device on the account then you must have had another apple device in the past that you used to set up keychain. Often times some users will turn keychain on and then realize they don't know what it is or what it does so they turn it ...
If signing in several times doesn’t resolve this and you can’t or won’t wait it out, signing out completely appears to get this prompt to go away.
iCloud Keychain refuses to setup on Catalina
You do of course have to deal with the side effects of signing out like choosing to delete or keep local copies of iCloud data and then setting up your iCloud ...
You can use https://privacy.apple.com and request a log of Apple ID details. May take some days.
In App Store, in the profile section, one can visit all previous purchases and hide/unhide purchases.
Easy way to see a list of all the apps I have installed on my iPhone This suggests using Apple Configurator and after plugging in, go to Actions -> export -> ...
Apple's Developer Documentation addresses this question. In their Human Interface Guidelines for Sign In with Apple they it states:
To help people set up an account and sign in, it's best to use the familiar buttons that Apple provides for Sign In with Apple. When you use the system-provided API to create a Sign In with Apple button, you get:
Only install Xcode CLI tool, since most of the ports work without Xcode although there's a warning during use.
Quote from Google Summer of Code 2019 for MacPorts
Phase out dependency on Xcode (done in the main repo)
MacPorts currently requires a full Xcode installation, even though a lot of ports will install just fine with the Command Line Tools ...
From apple support: You can't use a "rescue" email address to sign in to Apple. If you try to use a rescue email to sign in, you will get the error message: "This email address is not available. Choose a different address."
I had exactly this problem, and switching to my old mac.com email address fixed the problem.
I just got off the phone with Apple support for this exact question. Short answer: it can't be done.
Once you create an iCloud email account, that account can't be changed or removed from your Apple ID. The only way to delete the email account would be to delete the entire Apple ID account.