Just tested it again, selection "Display zoom" on the iPhone 16e with the following note.
Horizontal / vertical :
Mobile phone held horizontal, then the keyboard remains, a search with text input is possible. Keyboard surface large and comfortable. However, if I turn it vertically, the keyboard disappears.
Mobile phone vertically then the keyboard only flickers very briefly and disappears again, no input possible, but I then turn it horizontally and tap on search, the keyboard appears as described above.
Size of the mobile phone display:
6.1" (on iPhone 16e)
In horizontal, the keyboard seems to fit for the display.
In vertical it looks like the same layout of the display for the keyboard should be done but this does not fit for vertical at all...
Note:
What is noticeable is that in the "standard display" so without display zoom the MRA menu behaves very restlessly when turning so jumps and the keyboard behaves optically quiet when turning...