On all platforms, its home view is that of things you've consciously chosen to curate to see. The home view has both overt and subtle indicators to tell you to leave the app: all the stories to view no longer have the red outline, the post you scroll past says "You're all done".
The notion that society rewards high competence people who do not promote is also prima facie nonsense. That is not at all the case, not economically, not socially, nothing. If you want to be seen, you have to promote.
Because, let's be honest, your photo is 10x as valuable to your friends because you took it. If I'm looking at the universe of photos, the probability that you took one in the top 20 I want to see today might as well be a measure-zero set and the utility I gain from that photo is such that I need a discovery engine to bring it to me to be worth it. I won't look for it. The cost-benefit is negative as soon as I type in a single search term.
But that shaky handheld phonecam video of my friend fucking around with glow poi and hitting my other friend in the face? That is cost-benefit positive at up to 1 hour of search. And that makes sense, because it's a true social network, it's about the digital equivalent of your social circle.
Instagram is a magical social network. It is the circle of friends meeting for a Sunday afternoon hangout, your rave crowd, your dorm room buddies. It is happiness incarnate.