So, now Monk/Dragoon have to compete with yet another class?

[Pantz]

Dexterity is billed as a range exclusive stat so far so why is it fair that now Monk and Dragoon have to compete even further for slaying accessory drops?

No you don't. You still have to compete against 3 (or less) other dpsers in 8man content and 1 (or none) other dpser in 4man content. An extra class doesn't change a thing when party make-up doesn't change.

There will be no difference in getting gear now and when ninja is released, besides a larger loot table meaning less chance of a certain loot dropping.