Hello there!
Since one function is focused on security and the other on usability, both addressing distinct concerns, app protection policies and app configs enable organizations to apply these controls independently. However, from both an end-user and engineering perspective, I understand what you mentioned and it seems more logical for this specific function/config to be incorporated within app protection instead. There must be a rationale for classifying it under app config rather than integrating it directly into app protection. Now, given that Intune is a continuously evolving product, it's possible that we may see this functionality incorporated into Mobile Application Management (MAM) in the future. This is a relatively new development, and if changes occur, it wouldn't be the first time I see a feature/config migrating between different policy types or configurations.