Linking to your own stuff is ok in relevant contexts as long as you're not doing it too much, but from https://news.ycombinator.com/posts?id=billions I'd say you've been hovering on doing it too much.

HN users don't like it when people use this site for promotion, and they also tire of repetition. Keep in mind that there have been dozens of Covid-19-related projects posted here, so it isn't just repetition of your own links, but repetition of the category.