I guess the question is what is the ideal outcome of the interaction.
At least with respect to the other guy, it’s that he (a) understands why what he did was offensive/bothersome/bad, (b) takes that lesson to heart going forward, (c) maybe even communicates that to other people, spreading the good word, but at the same time (d) continues to have an instinct to help others, just tempered with better judgment and more awareness.
Were Ambi’s words the absolutely optimal way to achieve that outcome? Probably not. And not so much because they had a harsh or critical edge, but because of how he brought up the person’s motivation.
I finally figured out what it reminds me of… I’m a white guy. So at some point, let’s say I have some random interaction in a social setting with a black person, and I do something careless or thoughtless, and I’m clearly in the wrong. Say… I accidentally cut in line in front of him because I’m on my phone and am not paying attention. I mean, clearly I shouldn’t have, but it happens, doesn’t make me a monster. It’s open to debate what the response he could give would be which would most optimally decrease the likelihood I’ll do the same thing in the future… should he be polite? Should he be rude? Somewhere in between? Swear under his breath? Hard to say. But what I’m pretty sure it would NOT be is if he accused me of racism and said that I only cut in front of him because he was black. Even if it was in some sense true (and I’m not claiming I’m somehow 100% free of all racism), it’s such a heavy hammer to hit someone with that I’m going to walk away from the encounter fuming about how irritating it was that he played the racism card, not feeling guilty about having cut in line.
Of course that’s just me, and that’s just me hypothesizing about me, so, maybe I’m wrong… and of course it’s not like Ambi has some responsibility to act at every moment in every encounter in some theoretically optimal fashion. Saying “your actions weren’t entirely optimal” is a far cry from saying “your actions were bad” or “you suck”.