(a) HN no longer results in a dupe upvoting the original.
(b) If the first submission (or obviously submissions, plural) don't see any action, it looks like the dupe is now allowed.
(c) No one else seems to search first, so I don't see why you should. My question is genuine: suddenly this is being submitted lots of times - where are people getting the feed from?
I get frustrated with the number of dupes on HN, there has to be a better way of dealing with the way they take up space. Still, I have not better suggestions.
(c) The person who posted this does a lot of blogging / public speaking about software. He tweeted that he published this. He posted 2 of the links you posted. See: https://twitter.com/@searls
https://news.ycombinator.com/item?id=10203474
https://news.ycombinator.com/item?id=10203442
https://news.ycombinator.com/item?id=10203425
https://news.ycombinator.com/item?id=10203410
So many submissions, so few votes, zero discussion.