Well I have messenger lite on Android and they, as the parent says, "ask permission to listen to your microphone". Presumably they do voice chat, which needs that permission, surely.

Still no. If an iOS app is using your microphone while backgrounded, your phone's taskbar at the top of the screen will be red. iOS does not allow apps to use the microphone while the screen is off. The microphone thing is a myth fueled by paranoia and confirmation bias. FB already has plenty of data on you and doesn't need to run NLP on everything you say in order to show you relevant ads.

Maybe group-based, and some apps only get the selected.

I wish Android/iOS would let the user decide individually on every single file/contact/etc access, at least in an optional setting.

Would be interesting to see how many seemingly harmless apps start to break, I would expect similar results to surfing the web with a JS blocker.

For photos, I wish iOS would not require a permission at all in the case where I just want it to open an OS-controlled file picker and then give the app the one photo, akin to copy-pasting it. No reason to give access to every photo when only N are picked.