posts logic question!

I am wondering the logic of the 'top posts' in the hasagram of the instagram.
In the past, top posts were affected by 'likes', 'comments' and 'views' in a short time.
But not now.
It seems that there is also influence of following author of follower of posts,
Spam, and advertising posts also seem to be affected.
Please let me know if you have more information on this!

Following this thread, I'm also trying to understand how posts rank on TOP POST in a hashtag.