Then I got a replacement iPhone and reinstalled Instagram.app, and it defaulted to "show you notifications for everything we think you might be interested in" again, and I was too lazy to spend all that time relearning how to disable those notifications. I disabled the notifications entirely and now I open the app once a week or so to check in.
I had to do the same thing with Facebook years ago. Now I open it once a month to see who from high school got married in the last month and click the little "heart" icon and scroll until I get bored (~2 minutes). Can't trust Zuck with notifications.