Hi there, viniXD.
I heavily agree with you on the matter that someone should not belittle another person just for their nationality. At the same time, I'm also against generalization, which is something you seem to be doing. You're arguing that "Brazilians aren't as bad as you say", yet you're assuming that "gosh! What's up with all of these Americans hating on Brazilians?". In short, you're shooting your own argument in the foot by doing the exact same thing that these "Americans" you hate so much.
Get off your high horse. Just because you saw a couple of people online talking badly of Brazilians, it doesn't means all of America thinks the same. In fact, it's very possible that the people who badmouthed about Brazil were not even Americans, or might as well have been immature little kids. By making this topic, you're confusing people more than actually making a point in here, because most people don't even know what you're talking about. And you know what? They don't need to know. You could easily just ignore this vocal minority that "hates on Brazilians" as you say and just move on.
Really, from all the years I spent in this Message Board, I haven't seen anyone in here treating me like someone inferior just because I happen to be a Brazilian. Yes, you heard me, I'm Brazilian as well. I was never bullied over the fact that I'm Brazilian online, and do you want to know why? Because I don't make a huge deal out of my nationality. I don't go into servers using "(BR)" on my nickname. I don't get into servers and start asking "br? br? br?", desperately searching for other Brazilian people. I don't feel the need to tell everyone that I'm Brazilian at all, because I don't have any reason to feel this uncalled for pride of being Brazilian. It's a nationality, and no one is forced to care about it. You're just asking for people to get annoyed by you if you really put (BR) on your name for no reason.
Do yourself a favor and stop speaking for an entire nation, because there are two types of Brazilians on the internet. The ones who actually bothers to learn English properly and knows how to adapt to other communities, and the ones who are obnoxiously loud about how Brazilian they are and think everyone on the internet is forced to tolerate their "Brazilian" way of talking. The latter disgusts me a lot, and honestly, there is way too many of them. Even I am starting to get sick of Brazilians online.
You should make people's point of view on you depend on who you are, and not on your nationality. I hope that answers your question.