That being said... The fact that something failed one, two, or a hundred times in the past doesn’t mean it won’t work today. Things may be different today, or perhaps the approach may be slightly different. If Google can make bazillions of dollars using machine learning to optimize the ads displayed on a page, I’m pretty confident machine learning can be used to optimize the likelihood that you’ll upvote articles suggested by a bot.
The question of whether this becomes an echo chamber and you stop finding things that are interesting but outside of your current tastes is deep. There’s an old saying, “The best present is something you didn’t know you wanted until you unwrapped it."
Reading HN will also not expose you to non-hacker-related information. At the same time, it's always possible to make the stories you're more likely to like more likely to be chosen, and introduce some randomness to be exposed to the odd lower-rated story.
The question of whether this becomes an echo chamber and you stop finding things that are interesting but outside of your current tastes is deep. There’s an old saying, “The best present is something you didn’t know you wanted until you unwrapped it."