This is exactly why future tanks are likely to still share the same fending gear and overall appearance. There is already a lot of different armor classifications in FFXIV, making loot pools very cluttered, and so adding more is a bad idea. There's also a design benefit to tanks/healers sharing their armor which allows people who play those much needed roles to gear multiple tanks/healers. This gives them the freedom to switch tank/healer job fairly seamlessly (barring weapon).
Rather than cluttering the loot pools even more, a simple multi-glamour system would be easier and smarter to implement to solve the issue of tanks looking the same.
