Also, no one is asking you to accept that the Amarr are sparkly fun time religionists, because they aren't. No one is asking you to accept them IC as good people, because they aren't in the vast majority of cases, according to our western standards.
I just don't think that using IRL texts in arguments with Amarrians is fair, tbh. They're the ones who are RPing the religion, let them define the terms of the engagement, since they're the ones invested in it, and meanwhile you can just keep your arguments more general. I think thats reasonable, unless you want me suddenly defining how Wayism works, or something, or telling the Minmatar what form their animism takes.
"Fair" works both ways. It doesn't mean that one side gets to have exclusive access to a subject - that would be like calling a boat race where one team is rowing and the other has an outboard motor "fair". What's
fair is for everyone to have equal access to the same resources.
The fact that I chose to RP a given faction doesn't grant me exclusive rights to detail-build for that faction. Among other things, I'm as likely to disagree with another Caldari RPer on, say, the rules of Splinterz as I am to disagree with an Amarrian RPer on the details of the scriptures.
I'm all for an open season. If you feel you've got something constructive, interesting and realistic to add to the detail we're all building together, go right ahead. I'll call bullshit if I think it's "wrong", but I'll do it in-character. People believe that atheists are satan-worshippers IRL, after all. Wildly inaccurate, exaggerated claims about what other people believe is something that happens, why shouldn't it happen in-character?
In any case, if the Amarrian RPers get exclusive rights to define what's in their religion then that's not fair on me, because it opens the door to them producing the most wonderful, balanced, caring, enlightened and beautiful faith that has never existed.
RP in this context is a back-and-forth thing; either everyone gets to have their say or we wind up with a million mary-sues all standing in their corner sulking and never straying into somebody else's world. Whether or not any given person's say on the subject is picked up and run with, or dropped and ignored, is up to how good it is, how much it makes sense, and what depth it brings to the conversation.