This is a reddit problem in general. The problem is in reddit's design.

The idea is that people make a contribution--be it sharing something they found on the internet with the community or in commenting on something someone shared.

The downvote arrow was designed to support that aim by giving people the ability to get rid of spam or out of context comments. I think the developers honestly thought users would use it that way.

It was never meant to be a 'disagree' button. It's being used that way by people who want to participate but don't want to contribute meaningfully. That's why at this stage, Reddit ought to simply remove it. Reddit's original objective can be achieved using only the upvote arrow without letting people cheat the community.

All the issues you're describing (including downvotes) are being caused by people who don't think of the sub as being a community, and they don't think about what they do or say as impacting the community. It's people who don't care about anything really--because if people cared about the group itself and considered themselves part of it, they wouldn't bother with hateful things and might honestly invest their time and energy in contributing.