Does the Spirit Guardians spell stack with multiple casters?


Recently played with a group, where 3 of their clerics would cast spirit guardians, claiming monsters in the area had to make 3 wisdom saves for 3d8 damage each, potentially adding up to 9d8 damage per round.

Is this any different then trying to have two casters cast insect plague or cloudkill on the same area, or bless on the same individual?