I don't know anything about the jazz ensemble or the director, but take the email for what you will: a hurried response to an unexpected question from someone who is probably very busy organizing end-of-term music events. It's not really representative of Carleton professors. Some are very into technology and you'll get replies to emails at like 5 in the morning, but some old school profs won't touch their email on the weekends (and will instead ask you to call them at home). I'd say generally most professors aren't arrogant at all. I call almost every professor I've had here by their first name and I've found that they go out of their way to be accessible to students.