It is easier/more maintainable to text 75 people for their addresses every single year than keep an up-to-date address book

I suppose the fundamental assumption here is only needing these addresses once a year for a holiday card. That said, what I really want is some sort of iMessage app that pings a list and asks for their address or updated contact card.

Really? You still need to keep it up to date in the year, no?

It is odd that change of address is still so manual. It seems like there should be some universal way to automatically update your contact info for others and approve the recipient list from one place without the manual steps of resending.