Sorry, but to "disagree with the content" one provides on Hive, is not a valid reason for a downvote. A downvote is to fight against scam, plagiarism, personal insults or illegal content like child porn, but not just the use of free speech! In fact this is what Hive makes unique, that everybody can express his opinions, without being censored! If you attack this by a downvote, you directly attack free speech!
And like @vp-freelance said, you should have warned people that you would apply an additional political censorship filter that prevents rewards from posts of opposing opinions. In fact you better add this now on your explanation posts, so that people are warned in future and rethink if they want to send money to such a voting system!