Done right, it isn't. In other words, slapping a wooden ramp on the side of a house isn't technically Universal Design (more like an accident waiting to happen). You don't notice universally designed elements of a home until you're either enjoying or rely on them.
This project portfolio on Houzz represents a fine example of a few points I make regularly about Universal Design (UD). Now that more people are becoming aware of UD, traditional misconceptions come up that it is "ADA" or "will make my house look like a hospital". UD is for anyone, it's kid-friendly and, despite an obvious solution, not only for "aging-in-place" (A phrase we dislike). UD is a solution for enabling "aging" in one's home, or barrier-free living, but suited for anyone who prefers convenience and ease.