Many people in EA value personal productivity highly, and make it a goal to complete as many tasks on their to-do list as possible in a day. Some people (myself included, in the past) seem to tie up their feeling of self-worth with how productive they felt that day.
I think that increased productivity should mainly be used to reduce the amount of time we work each day, and not to get more things done. To live a truly fulfilled life we need more unstructured, unproductive time when we can be ourselves and do the things that we find inherently valuable and enjoyable.
Here are some things that I find valuable in themselves, and not particularly productive:
Running along a river or canal in the morning
Reading a history book in a café
Listen to classical music on the radio
Prepare an elaborate dinner for my girlfriend
Try all the different types of cheese from my local shop
Having spent significant time around both the EA and the LW community and having written several controversial posts and then subsequently talked with folks who downvoted those posts, I now have strong reason to believe that most downvotes are in fact "boos" rather than anything more substantive. When people have substantive disagreements with posts they more often post comments indicating that and just don't vote on a post either way.
I'm sure this is not universally true but it's been my experience, so when I see downvotes on a post that isn't obviously spam, trolling, or otherwise clearly low-quality (rather than in this case just not containing much content, a kind of post that is clearly not universally downvoted because many low content posts get either neutral or positive responses, which I must assume given their lack of content is a function of agreement with the idea presented), I find it reasonable to ask "why 'boo' at this?". Hence my comment as a possible explanation for more "boos" than "yays".
I agree it would be preferable if people didn't use votes as "boos" and "yays", and I think we could fix this—maybe by only allowing people who comment on a post to vote on it, although I think that risks creating lots of meaningless comments because people just want to vote, so there is probably some other solution that would work better—but unfortunately my experience suggests that's exactly how most people vote on posts and comments.