Hard disagree.
Science is about making hypotheses and testing them. It's fine to come up with a hypothesis that is untestable, especially if it's reasonable to assume that we may one day be able to test it. It's fine to even consider the probability that your hypothesis is true, absent the ability to test it, given whatever priors we have.
Sure, believing that we are in a simulation without evidence would be some form of religion. But merely acknowledging that it's possible that we're in a simulation... well, that's just basic science.
It sounds like you are doing something anti-scientific yourself: rejecting the possibility without evidence. This is one of the things that bothers me about hard-line atheists: just because gods are not falsifiable, it doesn't mean that they don't exist. I personally don't think they exist, but I accept that it's possible I'm wrong. Asserting that atheism is absolutely true and correct is no less a "religion" than theism is.
Consider this: if it is possible for our society, someday, to simulate a universe with the fidelity that we ourselves observe in our universe, then it is not only possible, but incredibly likely, that we, ourselves, are living in simulation. We can come to this conclusion using logic and reason. No belief or religion is necessary.