As an orc I’ve abandoned my duty to crush skulls for Orgrimmar to go torture lost souls for the Venthyr.
How much tending to the elements are shamans going to do in realms with no naturally occurring elementals?
We give up our duties all the time to save the universe in wow, the people of the Shadowlands are in no better a position than the people of Azeroth if the world soul is lost to an invader and used to trigger the end of days.
The end of living people means no more anima and the end of the cycle. It’s in their interest to protect Azeroth.