Yes sometimes the loudest voice definitely rises to the top and it’s annoying, but I also think it’s a condition that too many new members don’t know how to use the upvote button.
I also think it’s a symptom that HN does not allow enough people to use the down vote button. you could be a commenting member for years and not be able to downvote or you could be somebody who posts a few click bate links you copied from another aggregator and all of a sudden you have the ability to downvote. It’s pretty dumb.
From my observation it is hard to get to 501 karma points by the karma gained from submissions than through comments. So for comments every 1 upvote equals 1 karma. But for submissions, god only know what is the conversion rate /s. I think there are many factor. But I think this mechanism is to limit people creating accounts and mass down voting anything they don't like. So it is trying to solve another problem. However upvote power should be limited for new accounts (I don't know if this already the case)