Popularity has no bearing on validity, that's a common logical fallacy.

Correlation is not causation, but given people put their trousers on successfully, cross the street and go to work it's likely that they tend on aggregate to have a view of the world that matches reality. You can't use popularity of a view to ensure it's valid, but I don't think it should have zero sway, either. Or, to put it more precisely, I bet it's more likely that something the vast majority of people believe is true, is actually true.

Note: this does not mean I'm saying God/the tooth fairy/the loch ness monster/santa are real. It means there are more true things people believe than false.

Santa is real, FYI.