Required code owners for merge requests

We would like to configure required code owners approval for merge requests. Most merge requests can be approved by developers. Changes to certain files, however, must be approved by the users defined as the code owners. The feature comparison suggests that “Code owners […] can be set as required,” with Bronze or higher tiers. This was one of the reasons for us to acquire a Bronze subscription:

Indeed, we did not manage to make use of this feature. Approval by code owners is always optional:

The code owners documentation seems to have the answer:

According to this, a Silver or higher tier is required for code owners to be set as required. Am I doing something wrong? Or is the feature comparison misleading?