Square Enix should really address dungeon loot drops...

[Shurrikhan]

this isn't actually what was done. ARR's Striking gear (prior to gear added in 2.4) also has DEX due to Rogue and Ninja not being added until patch 2.4, hence why Ironworks, Dreadwyrm and WoD give separate Striking/Scouting gear, but Allagan/High Allagan, Syrcus Tower/LotA and the Soldiery sets (Gloam, Noct, etc) all have Striking gear which gives STR and DEX and is equippable by Rogue & Ninja

Sorry, I should have specified ARR as prior to content added after its second-to-last major patch, rather than just "ARR". Foolish me. Even then, as you've just pointed out, they were separated in exactly 4 instances/tiers, and not the remaining 38, nor any crafted gear prior to the final tier.

Either way, I have to wonder what's so damn much stealthier about the purple chest-wrap or navy sleeveless tunic as compared to the brown chest-wrap or tan sleeveless tunic as to warrant the bloat in grind and inventory space for a piece used by the exact same role as categorized in content (merely Melee DPS) and with the exact same defensive value.