Could have been anything behind the reasoning, I have found it better to not try to guess the motivations if you wait long enough people will spell it out for you. Either way it was a little presumptuous,There could be a new discovery tomorrow giving proof for or against, and I doubt on the whole it would change much. In this modern skeptical society either side would just declare the proof a hoax, or fraud or tampering, or flawed and on and on.
I try to just live as good as I can, if I die and there's a God then great, I lived a good life, helped people and did the best I could to be kind and spread good will. If not, guess what I still had a good life and those I leave behind will remember me for it. Why should we need God to live right and be good to each other? We need an excuse to be nice is that it?