Every profile on this site automatically follows Medium Staff. Yes, it is annoying. It was also one of the first ‘people’ I unfollowed. That got rid of the bulk of things I didn’t want on my feed.
But the rest of the algorithm isn’t about what publication pieces are in — unless you follow that publication. It’s about the tags they use. If you keep hate reading leftish issues so you can troll them, then your feed will get filled with leftish stories. Because those tend to use the same tags. Based on your interests is just that: stories tagged with the same tags as stories you read. I very much doubt Medium has an AI that scans stories for content and tone…It won’t know if a story contains “brainwashing propaganda” or something you agree with.