The initials in the avatar that apple shows for my account are inconsistent across devices

Yes, it was taking my name display order as a literal interpretation of the display setting in Contacts. I changed my Contacts settings to show first name before last but to sort by last name, and now the top left name in system Settings displays my first name before my last name. It's odd that the top left name in system Settings doesn't simply reflect what the Personal Information shows.

P.S. I do not have AI active on my computer.

Thanks for the tip.

I deleted My Card (it never regenerated on its own) but I have several other cards in Contacts for me. One has my image as the photo I have as wallpaper on my iPhone. Another one has the image it shows on my computer when I sign in. My home address house number was completely wrong in both of them and I don't know how that came to be. My street name was completely garbled which suggests true data file corruption to me. I set my iPhone card as My Card in Contacts and now while the image at the top left as Settings is still the old computer one, when I click on it the iPhone picture appears for my Apple Account one on the right. The names are still displayed as before so I don't know how it is assigning all this. The Settings display seems to be doing a literal interpretation of what Contacts displays, whereas the one on the right seems to know that the Contacts display is set to show Last First and knows to undo that. As I said, it isn't a big issue but I kind of feel I am losing control of what my computer is doing.

I know this isn't a solution but I notice that on my computer with Sequoia that in Settings my name appears at the top left showing Last First (not even a comma separating them), but if I then select Personal Information that it shows my name as First Last. I can see both at the same time and it makes no sense. I figure it's just a bug I'll have to live with, and it's mostly a cosmetic issue.