Whereas I see plenty of harm and plenty wrong with religion, though I separate that from the individuals who believe in it. We can agree to disagree on that. We can acknowledge that we think each other is wrong, which is kind of the point of this thread eh?
My own private theory is that Religion was the first science, the first attempt to explain the world. For a time it worked, in that it could be adapted to explain varying circumstances. For some people it still works, to varying degrees.
The danger arises from those for whom religion works all the time for everything, the ones who prefer prayers to antibiotics, for example. Even that is fine by me, so long as it is not forced on others. If you want prayers rather than antibiotics for your infection, not my problem; if you want prayers instead of antibiotics for a child's infection, even your own child, I'll make it my problem. And so on.
point of the above exchange that I typed out is to demonstrate how it feels for an atheist to constantly hear these questions and comments from theists which clearly demonstrate that they either can't understand that we don't believe in God, can't accept that we don't believe in God, or insist that we must be lying about it. I am surprised if you haven't encountered that. I see it frequently.
I'm retired and live rather quietly, and I can afford to be picky about who I talk to. Also, I learned a long time ago not to involve my ego in online conversations; I'll walk away from a jerk at a moment's notice. I'm too old and have gone through too much to waste my time on stupid.
But about that exchange of yours, why not have a little fun with it? Your responses should repeat your correspondent's statements and questions, but substitute their god for the god of your choice. Me, I'd use the Flying Spaghetti Monster, since I'm ordained in his Holy Noodliness' faith.
Or, simply explain that not having faith in their god is exctly like their lack of faith in, oh, Freya.
I pass the baton to you good sir

I came to this board a decade ago for the same reasons that you did; because I saw a group of people being attacked and maligned by my fellows and I wanted to see what they were all about. I wanted to dispel some myths for myself. In my case it was shortly after 9/11, and there was a lot of anti-muslim hate being slung around; most of which was completely unwarranted. In your case it is in the era of Daesh etc and not a whole lot has changed about this.
I learned, as you have or are or will, that Muslims are a vastly diverse group of people, including some who are liberal, some who are kind and gentle, and others who are quite the opposite. I dispelled for myself many myths that I heard anti-muslims say that I knew couldn't be true, and confirmed some others that I thought wouldn't be true. I spent about a decade looking into it, and my presence here was just a small part of that. I formed my own ideas and conclusions about it and though I always keep an open mind, my thoughts on it have now settled to the point that I have moved on (mostly to trying to understand the regressive left, who as a classical liberal totally perplex me).
If the baton is worth anything, I may sell it, or use it to stir my oatmeal.
As I said elsewhere on IB, I've learned that Muslims are just like everyone else, they just dress funny, and some of them have some strange ideas; I'm still getting my head wrapped around the one who is disgusted with Mickey Mouse's sex life.
Anyway, I plan on hanging around here for a while. Most of the folk here are pretty friendly, and they're far more interesting to talk to than the denizens of the two atheist boards I belong to.