That's offensively stupid, yet thats a standard message over in left America. It a quick excuse to dismiss a meaningful conversation about Christianity.
It's absolutely amazing (and very, very sad) that so many liberals - who most often have not the slightest idea what Christ actually taught or what He said, or of the significance of what He did - mock Him. They don't want to know - because they know that to know would mean to give up lives of sin and to turn toward God. They are afraid and insecure. We are called to pray for them.