And what was a dumb decision on the part of the conference organisers. It doesn't really have anything to do with why codes of conduct are a good or bad idea, though.
That's just vague hand-wavy logic. One time, a group of people vaguely aligned with X did something stupid, therefore X is a fundamentally bad idea. Obviously that's not true. If a conference organiser puts together a bad conference do you say that conferences as a concept are terrible? Of course not. You say "that was a bad conference". When an organiser overzealously applies inclusive rules you don't say "inclusivity rules are bad", you say "that rule is bad".