But they do: D558,757 and D670,286. Don't people remember Apple v. Samsung case?
https://patents.google.com/patent/USD558757S1/en
https://patents.google.com/patent/USD670286S1/en
Apple’s use of continuous curvature in iPhones came around iOS 7 iirc. I might be mistaken but I think they’re subtly but consequentially different subjects.