This sort of thing is an area of OS design which I dislike. Years ago I used to dream of the possibilities of fast, low-power, ubiquitous wearable Linux computers. And now that they are here, they are deliberately insecure and omit all of the good stuff.
Many of these problems of app access would be solved by simply creating another user account. Or being able to easily change permissions. Since Android is based upon GNU/Linux, and iOS upon BSD/Mach this should be the easiest thing. And it’s why I was tentatively optimistic that Ubuntu for phones might have been an improvement. This is not functionality they need to pay developers to include, it is functionality they were paid to remove.
I usually handle this problem by not using deliberately compromised social media services from deliberately compromised phones. But as the years go by, more people expect to be able to chat/text with me, so I will need to figure out something.
As for giving phone numbers in potentially sketchy situations, I use Gurgle Voice. If you use Android, Gurgle already knows your phone number anyway.
