Mastodon simply isn’t designed for discussions. It is designed to (micro)blog. People can react to your microblog, but if you’re not a well-known personality or your content isn’t relevant for the people who see your posts, that probably won’t happen.
What helps to build a followership on Mastodon is to regularly interact with people who post about similar things to your interests and who already have a big following. Then they might be inclined to know who you are, follow you and actually interact with your content/rebl9g it for their audiences.
I wonder how their AP implementation works and if it is compatible with the threadiverse software in theory