When someone talks they're telling you something about themselves, not about you. They might be telling you what they think about you, but that's something they think, not something you are.

In this case there are two things going on. One is the reason vs excuse, which is a blurry line vaguely separated by accountability and how much control you had over the situation.

The second and most important is that your boss is telling you he's an asshole who is more interested in making you feel bad than salvaging this situation and improving on the future.

That's the difference between nt and nd. Most nts will pick up on the fact that the boss is an asshole and there was never a correct answer. Nds on the other hand are more likely to internalize the situation wondering what they did wrong and how to improve future outcomes because they assume the criticism was honest and well reasoned and that there was a correct response.

The expectation of honest and productive exchange is unfortunately something assholes often abuse to bully neurodivergent individuals.