Your view wasn't suppressed, people can still read it no matter how bigoted it is. You have absolutely every right to state your opinions, and people have absolutely every right to call you a moron for having them. The rating is what the majority of people think of your opinion.
Maybe if your had any evidence to support it apart from people are using social media less implies people are tired of not being racist because you say so, you may have been rated higher.
Your argument makes no sense what so ever, in the first post you say you want to ban other races from social media, then you say censorship is bad, but you want stop other races from making posts. Oh right you probably think other races aren't people. So you should have no problem with them thinking you aren't a person either, and it is OK to kill you. I guess logic isn't your strong suit is it.
In fact since you where modded down implies that most people on slashdot disagree with you, since slashdot moderation is a form voting.
I for one do not use social media, because it is a huge waste of time. If it actually exposed me to more foreign people and their opinions I might use it more.