Out of curiosity when do you think this change occurred? Reason I ask is I follow 2 major accounts in my niche on SocialBlade along with my own accounts, and one friends account who is also in my niche. I noticed towards the end of January and into February the major accounts that I follow dropped off HARD on daily followers....I'm talking 1300+ daily to under 500 daily. My account and my friends account on the other hand have sky rocketed. For example I was gaining under 100 a day and my daily follower increase is has gone to 700+ daily since that time.
Now before I give the IG algorythm ALL the credit, I did increase my number of daily posts by double as well as started creating my own unique content during that same time frame which I know helped a lot on my account. The major account though has been doing the same thing forever so something triggered a penalty.
I don't use engagement groups...could never find one in my niche so I never get wasted my time.
The two images are screenshots from my SB account...one is the large authority account in my niche and the other is mine.