And then 2016 comes in — Instagram makes everyone follow the rules
2016 was the year when a new Instagram algorithm was introduced, according to which users would be able to see the posts they care about the most since they tend to miss a lot of content. Now the news feed isn't composed chronologically. Due to the newly introduced algorithm posts which gained the most engagement (likes and comments) were at the top of the news feed. So now it's the quality of the content that matters, and not the quantity.