Lady, gentleman or foreigner

Just now, I spoke to someone who'd been in the middle of a call with someone else when somehow the call was ended.

"Alright, I'll see who spoke to you. Did you talk to a lady or a gentleman?"
"No, I talked to someone with a foreign accent."

I was shocked. I didn't know what else to do but correct him and ask again if he'd talked to a man or a woman, then actually put him through to the guy he'd been speaking to earlier. Looking back, I should've talked to my manager first. As I'm typing this, my colleague is putting a lot of energy into solving the issue of someone who has just, without a thought, labeled him a foreigner over a man. I dare say that he's one of the most competent people we have working here.

I'm lucky to have the sort of awesome colleagues that are as outraged over this as I am. I sort of stopped doing these, but multiple people encouraged me to post this and I agree. Because this? This is not okay.