Nothing weird about it. The HN guidelines[1] make it clear, IMO, that while some self-promotion is fine, the intent here is NOT to use the site primarily (or exclusively) for self-promotion. The account that submitted the userplane.io link had only ever submitted two links, and both were to userplane.io. What do you expect to happen?

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.

> After a few more experiences like that, I've mostly stopped posting because it doesn't feel like the effort is worth it

Ironically this is exactly the wrong response. You should post more, but more stuff that's simply intellectually interesting, and not just to promote your own stuff. But if your only reason for being here is self-promotion, then you're right... not worth it. shrug

[1]: https://news.ycombinator.com/newsguidelines.html

Your account was created 5 hours ago, and you’ve already had two Show HNs flagged? That’s ‘email the site mods and ask for participation guidance’ territory. Perhaps you posted them under an account that wasn’t participating otherwise on the site and/or was named after a business rather than a person? In any case, bad form to re-promote your projects in an unrelated new post rather than reaching out to the mods. Adapt your behavior to be 95% contributions of posts and comments that are unrelated to your own projects/investments or else you’ll continue seeing hostility and flags to your work.