Discourse respects the order of tag groups in the category required tag groups setting, but there’s no indication of this functionality in the setting’s description. I ran into this issue yesterday when trying to figure out how to make a tag group essentially function as the “parent” of another tag group: What about an "advanced" or "guided" submission process for new topics in certain categories. It turns out that it’s as simple as adding the tag groups to the required tag groups setting in the order you want them to be displayed to users:
Assuming this is the way that restricted tag groups are expected to behave, could the setting’s copy be updated to indicate that the order that tag groups are added to the setting is significant?