I think there are certain industries, like health care and education that shouldn't be treated like for-profit ventures. It probably won't sit well with this crowd, but there are some things in life that should supercede wealth acquisition.
Similarly for education. The for profit schools get their money on the backs of the poor and those who shouldn't be in college. Obviously they don't get all of their money from such people but a large portion of it comes from these people. The profit motive in education is a bad one and should be avoided.
There's an assumption here that for-profit ventures perform worse or serve interests worse than non-profits. In my experience with non-profits, there's lower accountability, higher salaries with less performance, less accomplishing of the organization's objectives, and more corruption and politics. Nonprofits have historically done very poorly at their stated aims, and vastly, vastly underperformed for-profit companies in building up the world. Also, the majority of universities and schools are already set up as non-profits, which might be part of why they're so dysfunctional.
For profit education is great for giving a single individual specific skills they need that will make them money.
For profit education is unlikely to be interested in giving a person a "wide liberal arts background". And the thing about a wide background is that isn't worth much to the individual in terms of money. They might look back on their lives as having been richer for it or they might not. But giving a person a wider background is worth more to society as a whole, in everything from life being more interesting to politics being less polarized.
Non-profit, mostly, have standards for admission. The for-profits don't. They just want people to spend money. Faculty at for profit colleges get fired if their standards are too high. The for profit system is all about getting students in and making sure they never fail a course. Keep them paying. For profit motive in education as it currently exists is a disaster.
The root of the problem is that the rating system is programmed as a measure of /comment quality/ while people use it as an "I agree" or "I disagree" which is something different entirely.
We could add a separate counter for "Agree/disagree" and "quality comment" but you'd still need the cultural change. You need your users to value quality comments, even if they disagree with the content of those comments. Looking at an argument you disagree with and seeing it's merits is a hard thing to do yourself; it's a very difficult thing to get other people to do.
If we want to change things, I think a better thing to look at is maybe making who voted publicly viewable? I know I quite often upvote people I argue with (I mean, if your comment is worth responding to, surely it is worth an upvote) and I think if they can see that I upvoted them, it sometimes inspires conversation rather than argument.
http://news.ycombinator.com/item?id=117171
He is pondering changes to the voting system, as this issue is discussed every month or so.