I believe what you have heard about the tent end walls leaking was from much older PUs. When I was a kid in the parent’s had an early 70’s Starcraft PU, with real canvas tent walls. In that trailer you could not touch the canvas or it would leak.
We do not have the popup gizmos. We can touch the tent ends all we want with no issues of leaking. My kid seams to always have stuff pushed up against his bunk end tent walls.