It's not the belief in God that riles folks up. It's how many of those who believe act towards others that don't, like berating them with sanctimonious lectures such as this article demanding that atheists account for their lack of arbitrary made-up morals that religious folks parade out to flaunt their perceived superiority.
Its also the actual real harm religion has done to humanity, like fomenting endless conflicts, justifying brutal conquest, inquisitions and purges, blocking access to lifesaving medical care, subjugation of women to men etc.
Adherents of these religions that still exist today then have the audacity to lecture others about their 'moral' superiority and how they have all the answers to life. Apparently the meaning of life according to them is all to often to wage a campaign to convert 'non-believers' or execute those who resist conversion.
It's not the believing in God that riles people up. It's the tendency for these believers to whip themselves up into a frenzied paranoid mob that then comes for the non-believers to burn them at the stake.
Today it's a sanctimonious lecture/sermon about their righteousness and moral superiority. Tomorrow it will be The Republic of Gilead hunting us down when these 'believers' seize power and have their way, which is already well underway in the US.
The difference is that believers in Santa Clause don't foment genocides and murderous crusades killing and burning those who don't believe, or engineer coups to implement theocracies around the worship of Santa and the teaching of Santa's commandments in schools - at least not to my knowledge.
God might not be real, but some who believe he is are fanatical and dangerous - especially when they insist that separation of church and state should be abolished and that the church should become the state.
This is a dangerous mindset. The author is part of a movement striving for a theocratic future where we all must bow before their elders who claim to be the representatives of their God.
US 'Christian Nationalist' senators are already proposing legislation that would make it a crime to criticize or speak ill of their religion - akin to the blasphemy laws in place in Islamic theocracies. This is an egregious violation of the separation of church and state, and the first amendment.
Apparently, it was pointless to fight the Taliban for 20+ years when we've always had a 5th column of religious fundamentalists implementing many of the same policies in the US. Religious Fundamentalists won Afghanistan and they're winning in the US too, thanks to the likes of this author.
That's what riles us up.