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.
Review these pictures, do you notice the UD features? No, not unless someone points out, just as you wouldn't notice a wider doorway (until you're moving a couch). UD done well blends in and is preferred for maximum efficiency and control.
UD also isn't a "style" of house, any residence regardless of size, can be universally designed. Relate to UD applications as merely smart and proactive for any person of any ability.
So you might wonder, why isn't every home universally designed and built? That's what we think too, which is why we've adopted our mission of building Lifetime Homes and making home life easier.