This has been brought up for years. These threads should all be merged.
https://forums.zwift.com/t/ipad-why-can-i-not-see-riders-behind/546156
https://forums.zwift.com/t/ipad-screen-riders-behind-and-distance-at-bottom-of-screen/607554
https://forums.zwift.com/t/ipad-missing-the-distance-in-meters-to-the-rider-behind/535127