Moderators can’t do anything here, this system just means that there will be a lot more arguing because the replies will be negative, reagardless of the overall toxicity level. Enabling users to display their disagreement with a comment directly has many benefits, how that effects how many people will see the comment is something else, but this is one of the things I really liked about reddit. You can still discuss if you want, but often you don’t wanna waste time and/or get drawn too much into it. It is a more accurate measure of what people think about a comment.

What about showing both the number of up-and downvotes? This concept of ratios as we know it on twitter leads to the supporters only upvoting the post, but people disliking it upvoting the comments, which means the top comments always disagree. This fosters a climate of rage because the majority of intercations are negative this way. I’d rather just downvote and move on.