This, along with Zaria's Charismatic, access to Medic promotions, and her Lifedrinker vampires, is why she's an order of magnitude more powerful than the other two.
If you're using Final Fixes, Zaria switches Lifedrinker for Feast (not nearly as good in the long-term and the Mekara are much worse with it than the Calabim due to high unhealth and no Governor's Manors) and loses Charismatic, which Iram gains along with Industrious and religion-founding ability and better Aspirant usage, making him a competitive choice.
(Jamal can also use religions in Final Fixes, but he's still behind as far as traits/units goes)