I operate a larger instagram account (125k followers), and while I would rather die than apply the word "influencer" to it, I can confirm that it's very unlikely that this has to do with the content of the feeds. We have extremely regular content: 2 posts per day of artworks currently on view around the world. Sometimes we add thousands of followers a week, and our posts rack up tons of likes. Sometimes it takes weeks to add a thousand followers. There's no change in the number of people mentioning us, no outside source for the influxes. It really feels like we hit some threshold in the algorithm and then everything changes for a while. We've been pinned at 125k for a few weeks now after a period of fast growth. Nothing about our content or our natural audience has changed.