Instead of simply promoting your service right away (it often feels spammy), I recommend genuinely engaging in conversations until the right opportunity comes up.
I ended up turning that process into its own product: https://sparkflow.ai/
10/10 meta-promotion IMO
Hard to recreate but at the time I commented it was also the top comment with only a few others and it was on the front page. I've been a HN'er for a while and this is a rare situation to say the least if it's not a setup. I'm not willing to die on the hill and would gladly admit I'm wrong, I just see it as very suspicious forum spam as the most likely scenario