Syncing spinner is often missing despite showing stale unsynced timeline

### Steps to reproduce

1. fg the app for the first time in a few hours
2. view a room
3. see old content
4. see no spinner to tell you that it’s old
5. wait 15s or so and then suddenly the current room history is showed, without a spinner ever appearing (or if it does, it happens briefly)

### Outcome

#### What did you expect?

if the app is showing content which may be stale, it should always show a syncing spinner otherwise the user will incorrectly assume there are no bew msgs.

#### What happened instead?

No spinner

### Your phone model

iPhone 12 Pro Max

### Operating system version

15.4.2

### Application version

1.8.4 TF

### Homeserver

matrix.org

### Will you send logs?

Yes