So, following this train of thought - the armory and crafting mat UI also aren't content, just small QoL additions.
uhm, yes? you really wouldn't count them as content as in "enter a whole new zone with new horrors, discover a village teeming with quests and rich rewards an uncover a sinister plot below the graveyard!", would you? it is some interface fluff.
the thing is: same mobs, same maps. one life, victory conditions to be met in a time frame. it is content for a few hours until you have the wings.