These attitudes aren’t dying out. Her interviewers weren’t all older males; some who made sexist remarks were in their 40’s.
The patients who don’t acknowledge her as a physician are of all ages–including teenagers and 20-somethings as well grandfather/grandmother-types.
BTW, her residency is at a brand name New England academic center. She’s not anywhere near Texas.
(In fact most of more blatantly sexist comments she got were at schools in the NE and upper Midwest.)