I believe it is usually (if not always) an unproductive exercise to try to judge the actions of people in past ages by the standards of the present day. However, it can be interesting to look in a general way at the underlying trends.
I'm not judging people of past ages, Bill. Human knowledge and understanding has taken many millennia to develop. Part of that knowledge is the knowledge of how to build knowledge methodically. It's no more judgmental to note that the ancients did not have modern science than it is to say that they did not have modern trucks and houses. This is not to say that they were stupid or particularly ignorant. But - and this may seem radical - we have made some progress in understanding the universe in the past 50K - 200K years of human existence.
I don't know what a good reason is for believing in God (the only good reason I've ever been able to think of is possibly direct revelation, if such a thing exists, but even then there are epistemological issues) - but explanatory power has never been a good reason. OTOH, the existence of the multiverse, if it does exist, doesn't disprove a God. (Can't think of any way of doing that.)
One could argue that it pushes back the god of the gaps, but I don't think that's true either. OTOOH, it could be that so few of us have a sufficient understanding of the concepts (I'm not one of them) that it might as well be god (or magic) ... in the same way that tides or rainbows might as well be magic to a great many people.
