Sounds like the type of person who thinks of depression as the quintessential neurodivergence and leaves it there. Probably the most readily recognizable neurodivergence with de facto physical exhibitions is Down syndrome, but neurological disorders like Tourettes, Parkinson's, Huntington's, MS, etc can also come with highly visible and unsuppressable physical effects that very clearly mark people as disabled to others. And even that's not getting into congenital skull differences and stuff. There's a whole truckload of highly crude and recognizable physical behaviors that people use to signal mockery of intellectually disabled people that pretty readily prove that for most of society does believe that you can tell who's an r-word just by looking.