I respectfully disagree with this recommendation! As others have said, the idea of being "impaired" is not something that many Deaf folks are fond of.
Also, person-first language is actually kind of controversial in some communities! A lot of Deaf people see being deaf as an important piece of their identity and are perfectly fine, or even prefer, to be called a Deaf person rather than a person who is deaf. Same goes for a lot of autistic people/people with autism. That said, like any cultural norm, obviously there is variation from person to person and individuals may have different preferences.
In summary...this stuff is complicated! There are a lot of acceptable ways to phrase these things. I'd encourage writers to read articles on the topic of writing about disability and other minorities that are written by people who are part of that community. If you're talking about a specific individual, ask them how they prefer to be referred to.