Thinking about this more, I think the behaviour in this PR is more correct indeed. However, because our config fields weren't created with this in mind, I think we don't have them set up correctly. For example, after this PR, it would no longer be possible for a global admin to make an individual tenant private.

Therefore, I think a corresponding PR needs to be submitted to Hilary where we apply the following rules to our config fields:

- If the field can only be seen and set by global admins, but can be overridden per tenant: `{'globalAdminOnly': true}`
- If the field can be seen and set globally by global admins, but cannot be overriden per tenant: `{'tenantOverride': false}`
- If the field can be seen and set globally by global admins, but can be overridden per tenant and cannot be seen by tenant admins: `{'globalAdminOnly': true, 'tenantOverride': false}`

/cc @mrvisser: Does that sound reasonable?