Two Small Questions

So there's this article about an Oregon Baptist Church with a sign described as "anti-Muslim."

Pastor Michael Harrington placed the words on the reader board outside Belmont Drive Missionary Baptist Church. On one side it reads, “Wake up Christians, Allah is not our God, Muhammad not greater than Jesus.” On the other side, it says, “Only the Bible is God’s word, ‘holy book,’ Koran is just another book.” ...

But locals, including the mayor, don’t want to see the signs.

“I was really annoyed and sad,” Hood River mayor, Paul Blackburn, told KATU. “I am annoyed that in this political season there’s a solid case of ugly going on. I think it norms up this kind of behavior like ‘oh it’s okay to be a bigot now.'”

I have just two questions.

1) What is the difference between bigotry and orthodoxy? This is the official position of the Baptist church. There's nothing in the sign that isn't completely accurate as a statement of church doctrine.

2) What's the difference between Baptist orthodoxy and Islamic orthodoxy as regards what constitutes bigotry? Muslims officially believe the inverse of this doctrine: that there is no God but Allah, that Muhammad is greater than Jesus (who is merely another prophet, and a lesser one, according to Islamic orthodoxy), and that only the Koran is the direct word of God.

It seems the complaint here is either one of aesthetics or one of etiquette. Maybe it's just rude, or ugly, to point this out. But the only way believing in Baptist orthodoxy is "anti-Muslim" is if being a Baptist is anti-Muslim. If that's the case, than any expression of religious sentiment is a form of bigotry, for 'being a Muslim' is anti-Christian by an exactly similar argument.

Is the only way to be fair to everyone to be an atheist? Or is the argument just that it's fine to believe what you want provided you don't say it out loud?