I agree that, for the most part, those who rule via religion can’t be reasoned with. They are either so strong in their beliefs they will ignore you, or they are using religion as a means of control, in which case they will also ignore you. Most of the time in order to break someone from religion it can’t be done via direct intervention as it will only strengthen the “evil will try to corrupt you” type stuff many religions spout. I don’t know anyone that was really “debated” away from religion but I know some that simply gave up on it through their own realizations. This is why if you want to remove religion from society you can’t just go around attacking or banning it. You are only confirming their biases. You have to just educate the general populace and let them slowly phase it out themselves. Only time you should take direct action is with the crazy and violent groups.

As far as rulers BEING religious idk. There are some people that can separate their religion from their decision making but it also depends on the religion itself. Something like Christianity, catholicism, and similar such a religions I have doubts. There are too many rules and judgements. Those religions were designed around control. Developed for that purpose over more than a thousand years. Other, less strict beliefs idk. I haven’t much personal experience with them other than Taoism which isn’t ever really a religion per se. More like a general state of mind.