Upgraded to iOS 17, imesage archive downloading and filling iphone storage

I just upgraded to iOS 17, and am on an iPhone 12 (15 on order). For some reason, now iOS wants to download my full iMessage history (I have 33gb in the cloud) even though I’ve traditionally only kept one month on my phone (I keep full history on my MacBook Pro).

When I go into Settings>Keep Messages and change from “Forever” to “1 Year” or “30 Days” I get a warning that it will delete from all devices.

This used to not be the behavior, and now my phone keeps filling up — then I delete some old messages, and it downloads more until full, over and over.