Warrior is typically the most demanded tank at high end raiding if they only want to play one, and most raid groups dont need or expect their warriors to play other tanks or jobs. Not entirely sure why, but from my experience leading a raid group and recruiting for raid groups over every patch of the expansion, it is really difficult to find warriors and scholars that play their jobs well enough for savage content, as for dps, while not as demanded as war/sch, bard and machinest are equally demanded(most expect their bard to also play machinest and vice versa) and to some extent ninjas, tho not as hard to find as brd/mch.