Technically he implicitly said that superstition is a form of irrational thinking (few could argue otherwise with a straight face). He further implied that being deeply religious can be another form of irrational thinking.

What he did not actually say (though we can certainly infer) is that all religious thinking (or all deeply religious thinking) is necessarily irrational thinking.

If we merely grant that much deeply religious thinking is irrational, then I see nothing inherently wrong with suggesting that people who engage in one form of irrational reasoning might be susceptible to other forms.

Instead of commenting on religion, I will wager that people who claim to be superstitious tend to buy into horoscopes and homeopathy more often then the general population. That's not an offensive statement, is it? Yet what really is the difference between astrology and other things that we describe as religions?

So do you actually think that climate change denial and the rejection of evolution is not correlated with religious believe, or membership in the Republican party?