For #2, on mobile I'm constantly down-voting when I mean to up-vote, and vice-versa. (Before HN officially supported mobile, I sometimes ended up voting when I was just trying to zoom in!)
Taking a chance that people might not "think before voting" seems well worth it to remove a bunch of random noise generated by unintended clicks.
>#2 Without this feature, people are encouraged to think before voting, and only vote when they mean it.
People weren't doing that before. When they weren't voting for any pedantic or pettyreason they wanted, they were also unintentionally voting the wrong way because the arrows are just too small. Having a feature be irreversible doesn't somehow cause people to be more thoughtful about using it.
>#3 Without this feature, people are encouraged to use HN as a transient source of news and intellectual discussion, and not twitter.
People might be interested in what stories certain people find interesting. But it's just making a public version of an existing private feature (saving stories when you upvote them) so I don't think it would be that big a change in the way people have been using the site for a while now.
>#4 Without this feature, people are encouraged to go away and do real stuff until enough time has passed that the front page is new again.
Again - they weren't really doing that before. They were, however, complaining endlessly about stories they didn't want to see overwhelming the front page and comments section. Now that's a solvable problem. You don't have to see stories or comments on stories you don't want to see, and the people who want to see them don't have to deal with arguments about those stories' legitimacy.
>#5 Without this feature, people are encouraged to read or discuss an article based on its own merits, not just what appeals most to hivemind upvotes.
Maybe, although if they really want to encourage people not to act according to the hivemind (or, really, hiveminds, since there's more than one) they could do things like getting rid of visible scores, or letting users choose default sorts other than karma, or introduce more randomness into the front page (although dang said he tried that and the results weren't good.)
Or a really hard problem - how to get people to actually read the articles and not comment on the titles alone?
Tough crowd. I think all of them have their uses. The good news is you don't have to use them and how others use them is not really your problem. You're speaking about 'people' as if you speak for others, when in reality you only speak for yourself.
#1 This is the only good feature listed. It helps people skim comment threads for a relevant discussion.
#2 Without this feature, people are encouraged to think before voting, and only vote when they mean it.
#3 Without this feature, people are encouraged to use HN as a transient source of news and intellectual discussion, and not twitter.
#4 Without this feature, people are encouraged to go away and do real stuff until enough time has passed that the front page is new again.
#5 Without this feature, people are encouraged to read or discuss an article based on its own merits, not just what appeals most to hivemind upvotes.