I definitely agree with this, and actually, that's my whole goal with this article. I know people won't ever agree on everything, but I think we do need to find a handful of beliefs that we can all share.

In your first comment, you suggested "We are all from Earth' as a starting point. And in this comment, I think you've suggested another:

We should respect each other despite our differing beliefs, as long as our beliefs don't cause harm to others.

The thing is, many conservative Christians don't believe that. They believe that non-Christian ideas don't deserve their respect. And so I think that idea is dangerous, and liable to bring about harm to others, and so we should actively try to convince Christians not to believe that idea.

That's basically all I'm getting at. That we should actively work to convince people of good ideas. Which is ultimately what you are doing in your comment, too.