0.2% over two weeks is the kind of number where "Google update" is usually the wrong frame. Platform shifts move the needle but rarely take you from 1%+ down to 0.2%. At that level, the message either isn't being seen (spam/promotions placement) or the audience isn't right.
Fast triage: Mailflow seed test for actual placement, check Google Postmaster for a reputation drop, and confirm SPF/DKIM/DMARC alignment is still clean on both Google and Azure DFY accounts. Then compare open rates over the same window - if opens collapsed too, it's placement; if opens held but replies didn't, it's copy or ICP.