I haven't played FF14 but I'm surprised those don't have tags
my understanding of tags in general is for search-ability and for fans to find a way to filter their interests. for any set of parent/child copyright tags (i.e. "child" copyright tags that implies a "parent"; e.g. sequels, spinoffs usually), by the child copyright tag merely existing and having their own set of unique characters/designs that tag has value for fans of the parent copyright. e.g. someone interested in searching stuff exclusive to Pokemon Platinum doesn't have to search Pokemon DPPt + a bunch of tags for things exclusive to Platinum - they can just search Platinum
I get why DLCs aren't treated the same as sequels, spinoffs, etc.. I don't disagree in a gaming sense they're part of the same product copyright rather than a uniquely different copyright like even sequels/spinoffs with only a few minor additions are. but for danbooru purposes I still wouldn't mind treating larger DLCs with a fair bit of unique content as valid child copyright tags since fans ultimately see them as a Significant Unique Thing like Pokemon Platinum / Pokemon Emerald that might have value as filters for browsing on danbooru
but it's not like I don't see any harm at all because the slippery slope is defining what DLCs count as "large/significant enough" and that can probably be a headache a lot of the time. this isn't a hill I'll die on or anything for that reason. ultimately I'm kind of curious what evazion or nnt thinks even if I guess they disagree w/ me here