No, Brad is telling it like it is. Many band directors that were woodwind majors know next to nothing about brass instruments, and the quality of different brands. Most have only had at most 1 semester of class brass techniques. They will play it safe and go with a name like Yamaha, and with getting used horns that have gotten good marks with one ensemble, they know they can get good horns without worry. I majored in saxophone, but have been a brass player as well for a number of years and from as far back as high school, but I know most ww player teachers, don't have the background in brass I have, or another brass player would.
That being said on not knowing how things were in the past... I've had people get in my car and not know how to open the windows, they'd never seen a window that cranked up and down!