Your question might be alternatively phrased as, "We live in the 21st century; why do we still have six-year-olds?"
We are not all the same age, chronologically or experientially. It is not reasonable to expect OTHER PEOPLE to respond to things the same way YOU do.
Imagine that there is someone else - Carl Sagan, for example - who came to the same conclusion you did, but arrived there 20 years ahead of you. Are you willing to hoist yourself up for mockery because you failed to keep up with Carl Sagan? Of course not. So why should anyone else be hoisted because they failed to arrive at this destination at the same time you did?
Let the six-year-olds have their Santa Claus, their Easter Bunny, their risen Christ, their Buddha, their Shiva, Kali and Vishnu, even their Allah, as long as they're not killing all the other kids in the sandbox in his name.
So, to answer your question, "When is the human race ever going to rid itself of pie in the sky beliefs?"
Not for a very long time, possibly never. Our Monkey brains came from the "half-price" counter at Radio Shack; there is only so much we can ask of them.