Every post on this forum is reviewed before it appears. This is what that actually means, mechanically, because the rule is on the board and the mechanism is not.
The three outcomes
A model reads the post and returns one of three verdicts: approved, rejected, or unsure.
Approved means the post is public immediately. Most posts are, and most are public within a minute of being written.
Rejected means the post is not published, and the author is told why in a form they can act on. The reasons are specific: promotion, a referral link, recruiting, an unedited personal attack, a post that is nothing but a link.
Unsure means the model is not confident, and the post goes to a person. This is the case that makes the system honest: the model is not asked to be right, it is asked to be willing to say it does not know.
What happens when the model is not available
Nothing is published. A post whose review could not complete stays pending and waits for a human. The rule is that the model failing must never result in a post going live unreviewed, which means the retry job exists and the attempts are counted.
The two rules that are not about safety
Links carry rel="nofollow ugc". Every link in a post, no exceptions. A community that passes link equity gets spammed for it, and removing the incentive removes most of the spam before it starts.
No images. A remote image is a tracking pixel the reader never agreed to see, and it doubles the moderation work, because every image has to be looked at separately from the text around it. Markdown is enough: code blocks, lists, quotes, links.
The parts that are policy rather than machinery
Trust levels do not skip review. A member with a long history of good posts is not exempt, and that is deliberate: an account that gets sold or stolen should not come with a licence to publish unreviewed.
The daily limits are on the mechanism, not the intent. A new member can start two topics and write fifteen replies a day; the limits grow with what they have done, and they are computed from behaviour rather than granted.
Nothing is editable, only deletable. An edit would have to go back through review and would invalidate the notification that already went out to the people who replied. So a correction is posted as a reply, which is more honest anyway.