It probably exposes nothing at all to anyone if the Play Services are not on the phone or the relevant feature is not enabled on microG. But it is still a chunk

It probably exposes nothing at all to anyone if the Play Services are not on the phone or the relevant feature is not enabled on microG. But it is still a chunk of code that is partly run and that you don't control. It probably just does what it says (check if the service is present), but it is a black box.