It's a valid point, but there are plenty of fluffy stories about HN's favourite companies (which have included Uber in the past); how many stories about Tesla (the company), Uber, and the like are about their technology, and how many are breathless enthusiasm?
It does look a little rank when there's been heaps of "rah-rah Uber, disrupt, disrupt, disrupt" type articles in the past to have negative ones pruned.
If it looks that way, you should question your assumptions, because that's not what's happening. What's instead happening is that a controversy-du-jour is spawning lots of little stories, and the mods are working to make sure they don't co-opt the front page, which (because it is a linear list of individual links) is especially vulnerable to controversies-du-jour.
It does look a little rank when there's been heaps of "rah-rah Uber, disrupt, disrupt, disrupt" type articles in the past to have negative ones pruned.