I understand what you're saying, but in a general sense, a person with good "Reputation Points" can be seen as contributing positively in the communities they are in. Even posting a controversial opinion and getting downvoted to hell (which I have done before on reddit) won't kill a person's Reputation Points / Karma. I'm still torn on whether it's a positive or not, but it can definitely used as an indicator of whether a person is being a positive member of the site.
However, @PositiveNoise brings up some of the negative points as well. Another being that it reinforces an echo chamber of ideas and stifles discussion, with unpopular but well-fashioned arguments being downvoted because they're disliked, not because they're harmful. And further, repost bots got tons of karma on reddit, upvoted by people who didn't see it the first time, which reduces the quality of the sub / community / magazine by burying OC that couldn't compete against an already proven successful picture / tweet / meme / etc.
It's a conversation. There are arguments for both sides imo.