But that is an app problem that you can’t really solve from the OS point of view. And more importantly if you are using W/A Facebook will know all your details

But that is an app problem that you can’t really solve from the OS point of view. And more importantly if you are using W/A Facebook will know all your details from the other end. If only takes a few people in your social network to share dats with Facebook or Google for them to be able to construct your entire social network quite accurately. You can do this experiment yourself, take one of each: a colleague, a family member and a friend combined is all it takes to expose high double digit % of your entire social network and for most people 2-3 of each type would likely expose all of it. And that isn’t something Apple can protect you from the only option is to not use any such services and not to be in contact with anyone who does and that isn’t something most people would are willing to do.