alt Hacker NewsThe guidelines already cover this:
> Please don't use HN primarily for promotion. It's ok to post your own stuff part of the time, but the primary use of the site should be for curiosity.
https://news.ycombinator.com/newsguidelines.html
I assume that users who primarily/only post their own stuff and get flagged a lot reap the consequences, there's plenty of spam filtering on here thank goodness.
Those who slip promo of their own sites among a stream of other legitimate submissions or just space it out enough across multiple accounts can fly under the radar for years. People know how to game HN and already are, e.g. https://news.ycombinator.com/item?id=49517728