I think it’s just the algorithm, not anything nefarious. I don’t work for Medium and don’t know exactly how the algorithm makes decisions, but from what I can gather, the reason you see Johnstone’s posts is because they get a lot of claps from readers, which means the algorithm would bring them to your attention if people you follow clap for them, if you follow some of the tags on the post, or if you frequently read/clap for articles on similar topics.

And you’re welcome. Thanks for reading.