Everyone believes in God. It is instinctual. There hasn't ever been a culture without belief in God.
With the discovery of DNA, (and many other things) we have what statistics PROVE is evidence of intelligent design.
God never acknowledges the existence of atheists in the bible. He only says, "The fool has said in his heart, there is no God."
God is revealed from heaven against all ungodliness and unrighteousness of men, who suppress the truth in unrighteousness, 19 because what may be known of God is manifest in them, for God has shown it to them. - Romans 1
People know that God exists, they just suppress it. Regardless of the nice things that unsaved people say from time to time about God, the reality is that they really don't like him. This is because psychologically we know that we are God's enemy and he ours - by nature. We cover it all up with religion, good works, pride, more good works etc.; it's all so tiresome.
The old vehicle can't be fixed. That's why Jesus said that we must be born again. Many people are just fine with their first birth and are not willing to go through another. The watchtower offered us a way to be religious without going through the circumcision of the spirit and getting born again. It seemed like something that we could control, and not too weird or radical. It didn't work.