there's no need to "optimize" it already has the basic loop. stochastic reward (interesting news, interesting comments/replies), gamification (points go up!), and no real social interaction. (no connection, some performative elements, ie. comments are written not just to one known person or a small group of people you know.)

the things you mention all exploit this loop for monetization. I agree it's great that HN is not, but that doesn't mean it won't tickle our brains.