Ok. I have been thinking more about your essay.
Is this somehow related to capitalism? I deleted Instagram for the same reason I turned off notifications for Facebook or keep my phone on vibrate. I don't like being sucked into my phone or having my day interrupted by a ding.
Both Instagram and Facebook are trying to get me to look at them for their profit. Also (like you said) a lot of the boob/butt content on IG is OnlyFans people trying to entice me into a subscription. Essentially I am watching advertising. And with Instagram there is something like plausible deniability (even to myself). I'm not saying I am a victim here, just that the content is designed to suck me in. This is transactional and not really human.
I also think there is something new about the smartphone. When I was growing up I would have to hide magazines or (later) VHS tapes. Then I would have to have nobody around at all in order to secretly look at them. Now I can just turn my phone screen away from others' eyes and be ready to make it change to something else. Again, not to say I am being victimized by my phone, just that this is a level of access that my teenaged self never dreamed of.
Even after I deleted IG, I still am on my phone more than I care to admit. And since IG is not just feeding me reels, I end up sometimes seeking out other websites. I am bored and sometimes lonely and instead of doing something about either of those things I look at my phone. This is the tie-in to capitalism because I could be out there fighting the oppressive systems while connected with real humans, but instead I am mostly just an individual consumer.