Patrice Oneal did it best.
He hit the nail in the head. Seth has an ego.
Yeah, it's been long well known Seth MacFarlane has an absolutely enormous ego to the point it just gets tiresome hearing him speak at points. His mouth piece episodes as Brian in particular has pissed plenty off because for all of his shit towards religion, its literally the basic bitch atheist guide to it that has been poked at, laughed at, mocked, etc.
It's hilarious to see people like him act so up in their own ass and still get shit wrong(he literally believes in science despite it being sell known not only many scientists are religious, they actually use as an impetus of why we may not know everything about the universe)