Did you ever read the Old Testament and think, wow, this is pretty horrible? The carnage, slaughter, taking slaves, killing every man, child and even animal of different tribes, taking virgins for yourself by force, all commanded by God. I know Jesus came with a new covenant and so on but at some point in time the same God sanctioned some pretty horrible stuff by our current sensibilities. A lot of other strange stuff like seeing your father naked by accident requiring death (IIRC). I don't think a Christian would say these were mistakes and sins.
If we were to compare the OT with the Koran, the OT is not any less violent and brutal.
Is there a concern that our society and culture will be based on the Old Testament?
The New Covenant is not just a "so on".
There are a lot of horrible things in this world. I've mentioned many times before that I have a lot of issues regarding a God. Of all the worlds that could have been created why this one? A world in which the bad outweighs the good. Wasn't things fine enough before this great creation? As far as I know, I was doing fine before I was born. I didn't ask for this and if given the choice I'd take a pass. It's not worth it when all is said and done. And I'm one of the lucky ones. I always say that the more interesting question is not whether or not God exists, but is God good? But I'm here now and fortunately, life is short.
You decide what kind of world you think you live in. The choice that you make will determine, whether you know it or not, your metaphysics. How you perceive life and any sort of cosmic justice will shape the kind of person you become and are. If you believe that everything around you and everything throughout history including the beginning of life is simply a random concussion of molecules that somehow appeared out of nowhere. That the concept of good and evil is meaningless and simply a matter of personal opinion which can vary widely among individuals and even yourself depending on the circumstances. That a Mother Teresa and a Stalin share the same fate. Then you will agree with Dostoevski who wrote in the "The Brothers Karamazov"
"That without God, all is permitted." For without God, there is no such thing as morality. Just personal opinion.
People like to laugh at the absurdity of a God creating a universe but feel it is perfectly reasonable to believe that the Universe just suddenly appeared out of nothing.