https://www.aap.org/en/news-room/aap-voices/bill-maher-can-do-better-we-need-real-talk-about-vaccines/

He's also a genuine Islamophobe, but as you correctly point out, that's part of his anti-religion schtick: he hates all religious zealots.

Not sure what the claim about being racist against Arabs is all about, especially since Arab isn't a race.