@marcguay I would not recommend that solution either, specifically because it gives all website visitors subscriber access. There are many vulnerabilities found every day that are only an issue when an authorized user with subscriber access or above is logged in and this makes all visitors authorized users.
I failed to mention what you call the correct way in my first reply, and that is the way I would do it.
I would only add that you could use acf/prepare_field filters on both fields to 1) Remove the “other” option for logged in users and 2) remove the extra text field for logged in users.
