Question: How do you know that those other players didn't get banned? Unless you actively stalk their profiles (which I advise against doing and even then it's not a fool-proof way of seeing if someone got banned or not) you only get the "a player you reported has been banned" message if your report was the straw that broke the camels back. It's not a great way of getting feedback I know, but that's how it works. At any rate, other people behaving poorly will never excuse your own poor behavior, hence why you received a punishment (an escalated one in this case for telling someone to kys).
While I don't condone those other peoples poor behavior (assuming you're telling the truth anyways), understand that under normal circumstances it's consistency x severity that determines if someone gets punished or not, which may (keyword: may) be why you received a punishment first. Next time just mute, report and move on instead of fighting fire with fire.