So ive just noticed this issue on my iPhone XS too. Have been frantically googling like a maniac to see if there are any fixes on the internet for this. Turns out not much. Phone was perfect this morning, was left for a while and when i returned i got this issue.
Tried everything i could think of, restored as a new iPhone, backed up and restored. Even reluctantly updated to iOS 14.5.1 with no change. Hard reset it, checked if it was an app issue but nothing. Initially i thought the issue was hardware related after dropping it on carpet from waist height (im 5'8). iPhone has always bee in a case and always had a screen protector so no damage occurred.
Like most first i couldn't use the keyboard properly the P and backspace button wouldn't work. Then i jumped on safari and noticed i couldn't scroll using the right hand side of the display. Opened note and used the drawing tool, noticed i could use the whole screen except the right hand side again.
When rotating the screen either left or right, the right hand side of the screen works without issues which makes me more confident that this is an issue with the software and not hardware.
So i used the apple chat as the website wouldn't let me get someone to call. Turns out that i would need to get my self an appointment for the genius bar and bottom line would need to pay if the device needed attention. So i thought scrap that.
Now im stuck for ideas. Can't afford to pay out for a repair might as well just upgrade.
So my thoughts have already been voiced by those before me. How do we get apple to recognise the issue and resolve it? I read that there was a similar issue on the iPhone X.