The users with Stream permissions will get only Stream access. To get the users App Object you need to create another Rule to set the App Access and then there select AND App.Stream <Stream Name>.
Similarly, One need to give the users access to AppObject with which the user get access to the App Sheets and other objects. For the one need to create the Security Rule for AppObject and set the permissions for the user group as AppObject in <Stream Name>.
This way the users get the guided access to the Apps and App Objects within the Stream.