I was working with a question that was a part of the FAQ, and it wouldn't let me submit the changes because it "must include one of these tags – [bug] [feature-request] [discussion] [support]".

Do all future edits to FAQs also require one of those tags? This means that you are effectively limited to three tags specific to the question's content, and might have to remove a good tag in order to make room for [support] or [discussion]. Doesn't FAQ already imply [support]?

Can questions already tagged as [faq] (a locked, moderator-only tag) be exempt from required tags?

Though I of course don't know the backend implementation, if [faq] was added to the list of required tags (and the missing-required-tag error message cleaned up so that non-moderators weren't prompted to use it) while still being a locked tag, then any 2k user editing an FAQ would "meet" the required-tag requirement, without allowing non-moderators to add or remove [faq].