It would be interesting if you could find this matter of fact “requirement” somewhere. I looked a while back years ago when there was talk of excluding AUs. There was some gnashing of teeth on “blogs” about divorcees (primarily assuming the wife would never have any employment or income, so therefore it’s sexism!), but there’s obviously no requirement to give them extra credit compared to similar wives with husbands who have poor credit or vs newlyweds. People with no credit history will have no credit history. That’s how it still works even with spouses if they have no individual credit unless one is an AU or joint account holder on the others’ account. As far as I know, there’s no requirement to fill in a fake credit file for a widower or divorcee who was NOT an AU on any of the spouse’s accounts. Do you agree with that?
I can’t find any articles now referencing those temporary changes since it’s so far in the past. I could swear I read one from one of the CRAs stating that they decided to include all AUs again due to good-risk pool shrinking too much and that all children/relatives/spouses actually had a pretty good indicator of credit worthiness if an excellent credit relative trusts them enough to add them as AUs, so they decided it better represented risk scoring overall to add them back in. The only reason I remember it somewhat clearly was because the partially implemented and then rolled back changes were around the time when I had myself added as AU to a parents’ account that was opened when I was a toddler. Gave a nice bump in score to remove the deduction for a reality new “earliest opened account”.