[Bug]: Onboarding - After disabling Profile Sync, the feature is enabled if I go back to Edit default privacy settings

### Describe the bug

Whenever I am onboarding, if I edit the default settings to disable Profile Sync, if I go back to editting the settings, I see that Profile Sync is again re-enabled

### Expected behavior

Profile Sync should remain disabled, when I disable it

### Screenshots/Recordings

https://github.com/user-attachments/assets/58bab8c4-3cf1-401c-a706-13775e90d98d

### Steps to reproduce

1. Start the onboarding
2. Go to General settings
3. Disable Profile Sync
4. Go back
5. Go to General settings again
6. See Profile Sync is enabled

### Error messages or log output

```shell

```

### Detection stage

In production (default)

### Version

12.12.0

### Build type

None

### Browser

Chrome

### Operating system

Linux

### Hardware wallet

_No response_

### Additional context

_No response_

### Severity

_No response_

Start with the onboarding General settings flow and reproduce the Profile Sync state change in version 12.12.0 using the listed steps. Trace how the disabled value is retained when leaving and reopening Edit default privacy settings. Done means Profile Sync remains disabled after returning to General settings.

Written by the indexing model from the issue text.