> […] you have the freedom to not install them

What if Instagram decides to require side loading to install their app — in order to increase ad revenue?

Don't use instagram, simple choice))) Or, hear me out, you would be able to use insta in the browser with iblock installed so that you don't have ads and part of tracking!

And what about the users who wish to use Insta for sharing photos on socials, but don’t want to allow fb wholesale access to their data? Why are their concerns so glibly ignored?

ask fb? it's the business of the fb to distribute their apps. Or, you can use insta for sharing photos... in the browser, and even block the ads.

They don't on Android, why would they on iOS?

BuT wHAt iF TheY CoUld?