You've missed the point, nobody claims to know the absolute true nature of the universe but it's 99.99% certain that what ever God or religion you believe in is wrong regardless.

After observations it is only speculation. People look down on religious views because so much of what there is, is a view on the nature of the universe built on ideas by people 2000 years ago who thought the earth was the center of the universe and that what ever God created the universe must have made humans and for a very specific reason.

Even taking the assuming that there is a God, of all the religions that have existed or could exist there is pretty much no very chance that those currently followed were developed at a time that could not have been right because they lacked the tools and understanding of what kind of universe they were even in. Modern ideas of the universe have come so fast that the idea of God being dead seem much more reasonable looking at what all our old ideas of the universe and that God that created it then the thought that if there is a God we had a incredibly naive understanding of what they were.

God existing or not, almost all modern religion was created from very wrong ideas about the universe. That's why there are people who might look down on those whose views come from ideas from so long ago. A lot of religions try to claim the modern universe is compatible with their views but you have to understand that from a outsiders view the religion does not fit the other way.

There would probably be more scientifically minded people who believed in God if there were a longer standing religion that described a God built off of modern ideas of we know about the universe, biology, and physics