For clarity, this is how you search HN using Google:
And honestly, I love that approach. In my time on HN features have rolled out slowly, and you can tell that they were selected very carefully as being important quality of life improvements that don't fundamentally change the interactions.
Most features that people propose that HN needs are likely to substantially or subtly alter the dynamics, with potentially catastrophic results over the long haul.
I use HN replies (and RSS)... but very few others do, so the the change of getting a reply to this comment is low, even though I got here within a day.
When I say a system, I'm including everything, including the community. It's not any one part of HN, it's the way all the parts interact. Seemingly small changes can have a dramatic impact on the way the system operates, which includes the community. Suddenly different voices become amplified while others feel marginalized, and it's hard to predict if that will be a good outcome.
I'm not saying that it would for sure be a problem, but I sympathize with dang wanting to be very careful before introducing something like that.
All and all, reliving prior content and/or having a complex multifunctional interface would take away from the centrality and freshness of the home page experience.
I have wondered if dang would be open to allowing community to contribute to various approved feature additions; for example, better search, night mode, duplicate detection, etc.