Pika, your issue is with the message more than the messenger. The question is how I can be more effective sharing the message without creating unnecessary barriers.
You can be more effective if you understand and know how to handle your competition, thus making your message more convincing. A good discussion anticipates possible refutations. It doesn't appear that you do that much. If you can't prove your points of discussion, you will get no where with people who need that proof. If you are so convinced that you are right, then are you ready to debate non-believers? Can you prove anything to us?