Earlier quoted context omitted.
I think its just that everyone who doesn't run a mail server hasn't had to deal with this shit so finds it hard to believe that their precious email providers are being a pain in the butt. That is until you get a court summons after an invoice was sent several times and never got there because some fuckwit mail policy just blackholed it. This stuff does happen and when it does its costly.
I think there needs to be a more substantial karma gate to downvoting (10 000+), I'd be fine with falling out of that category myself. I've only been interacting on HN for the past year or so, but lurked for several years prior: the community has been becoming a lot more "redditish." I nearly always agree or can be convinced by the higher karma users, but the fresh users seem to be defaulting to reddit-level argument…
Also, Reddit is cool, and there's ton of quality discussions - usually under particular subreddits. For example, I love /r/KerbalSpaceProgram for a perfect combination of being large, friendly, fun, and full of people willing to teach each other some more advanced science.
To address your point: I think current downvote gate is fine and adjusting it up won't really help much. What would help (though I don't know how to achieve that) is people realizing that when saying anything controversial, you might end up getting a bunch of downvotes immediately, but the score usually settles to a reasonable value within an hour or two. It takes time, but one just has to get used to it.
TL;DR: karma comes and goes; look at it through a low-pass filter, to filter small variations.