Why Isn't My Firestore Realtime Stream Updating with Stricter Security Rules?

I'm experiencing an issue where my Firestore realtime stream stops updating when I implement stricter security rules. With less restrictive rules, such as those allowing read and write if the request time is before a specific date, my stream updates as expected when changes occur on the server or in the local cache.

Example of working security rules:

FIREBASECopied
service cloud.firestore {
  match /databases/{database}/documents {
    match /{document=**} {
      allow read, write: if request.time < timestamp.date(2025, 12, 14);
    }
  }
}

However, when I apply more restrictive security rules that enforce the user’s UID to match the document's author UID, my stream does not update. Interestingly, using a direct get() call still returns updated data.

Stricter security rules example:

FIREBASECopied
service cloud.firestore {
  match /databases/{database}/documents {
    match /{collection}/{document} {
      allow read, delete: if request.auth.uid == resource.data.author_uid;
      allow create: if request.auth.uid == request.resource.data.author_uid;
      allow update: if request.auth.uid == request.resource.data.author_uid
                    && request.auth.uid == resource.data.author_uid;
    }
  }
}

Using a get()

DARTCopied
var doc = await FirebaseFirestore.instance //
    .collection('lists')
    .doc(id)
    .get();

Stream usage in Dart:

DARTCopied
_stream = FirebaseFirestore //
    .instance
    .collection('lists')
    .snapshots(includeMetadataChanges: true)
    .listen(
  (QuerySnapshot snapshot) {

I would like to understand why the realtime stream does not trigger updates under these stricter rules and how I might adjust either my queries or the security rules to enable continuous updates. Any insights or solutions would be appreciated.