Fixed it. I turned off Apple Silicon Mac Availability in the Pricing and Availability section of the app.

I had this same problem. I fixed it by doing this: https://stackoverflow.com/a/66609391/8948894 Basically, in the appstore connect go to your app then under the Pricing and Availability tab, I unchecked the Make this app available for Apple Silicon Mac Availability, and now my iPhone screenshots show first and it removes the "Designed for iPad". It took a couple hours to update on the store though.