You also have to keep in mind the time frame for those advancements though as well. After all, we have only just now had our first expansion to XIV 2.0...essentially putting us at the Zilart stage of XI by comparison...or CoP if you were to consider the 2.0 the equivalent of the bundled Vanilla XI/ZM with the worldwide release. Regardless of which way you look at it, that means you should be backing out much of that added storage that didn't came into play until something like 4 or 5 years later in it's development.
Edit:
Found a link to the timeline for the important patches and such organized by expansions. The link is to the initial launch game's page. You can click the links to each expansion up near the top under the blue bar: http://ffxiclopedia.wikia.com/wiki/Category:News/FFXI
Notice that Mog locker wasn't even introduced until TAU in 2006 (3rd expansion), and only had 30 slots with quests to expand it to 50---didn't get up to 80 until June of 2007. Note also that the gobbie bag was STILL limited to 60 slots. WotG got us to 70 in November of 2007--it didn't hit 80 until May of 2009. So it wasn't until nearly 7 years after the game released that we had all 80 slots implemented across 5 containers (bag, safe, locker, sack, satchel). Remember, the game launched in 2002. It took ~7 years and 4 expansions to reach that point. The game had 20 jobs at that point, some of which required you to not only carry situational gears but also tools and ammo as well. And lets not forget the extensive crafting (8 + fishing) and HELM activities as well--and to gather you had to carry consumable tools for each specific activity (axe, scythe, pickaxe, pole and baits/lures). Let's not forget that to craft you had to have crystals (8 varities mind you, and you could have clusters of them as well) in your gobbie bag in addition to the items needed for the crafting, as well as equipping any gear that might augment the crafting. And there was also food, potions, and meds on top of that---still limited to an 80-slot container for immediate usage.