This is full of terrible advice. Password rotation is an outdated practice.
Don’t ever reuse passwords with “zones”, just use a password manager to generate long and secure passwords for every account. Then enable MFA wherever possible, and Passkeys where they have been implemented.
Then have a recovery method for the password manager stored in a secure place.
Imagine you have a book that’s written in Korean. If you gave it to me and asked me to read it out loud, I wouldn’t be able to make sense out of it. If you gave it to a Korean person, however, they could read it perfectly fine.
The book itself hasn’t changed — just the person reading the book. And that person has a different set of skills (or instructions, if you will).