With one of the recent iOS updates Apple moved from incoming calls taking over the entire screen to the banner you are seeing. It is supposed to be less intrusive when other apps are on the screen. This is now the standard for incoming calls, as far as I know, when another app is in front.
On a Mac since 1984.
Currently: 24" M1 iMac, M2 Pro Mac mini with 27" BenQ monitor, M2 Macbook Air, MacOS 14.x; iPhones, iPods (yes, still) and iPads.
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