Those strong magnets could interfere with the camera itself.
If you want to know what I mean check out this video:https://www.youtube.com/watch?v=HdIBhV1HScY
Asus ROG Gaming Phone Teardown - Are the vents even real?
At Minute 4:39 he is pushing the camera to see it's moving.
At Minute 4:56 he shows the magnetic effect and the camera lens moves around which is bad.
The P20Pro has stabilized lenses too.