That's not overall in Brazil. I live in Sao Paulo and it's certainly not rude to arrive on time or closer to that time. The time is usually a reference of "arrive after that time" and people will arrive in the hour or two after the time set. Usually closer friends will arrive earlier and not so close friends will arrive late because the party will be already full.
I have no idea where the author got the generalization that this is a rule "everywhere in Brazil". It's at most more or less a custom in Rio , and no other places that I know of. In southern Brazil not arriving within half hour of the appointes time is in fact disrespectful Besides this is only for social appointments . Try to arrive a couple hours late for a meeting and you'll find yourself talking to your boss aboi…
They have a word for it too: jam karet, or "rubber time".