The Wishlist topic that @dave27 alluded to includes a more fleshed-out explanation:
You can Vote in that topic above the initial post, and share your ideas and use cases in the comments.
According to one of the founders earlier this year, this is supposed to get some attention:
There are a lot of asks in that particular Wishlist topic, though, and microSD recording access for shared users is only one of them, so I have no idea what their priorities might be when it comes to actually tackling the issue of various permissions.
