Hey, it takes a lot to get fired from CNN, and Reza Aslan managed to do it (although his not so long ago on air brain eating stunt may have contributed to it). Pooper Cooper and Jake Crapper are probably safe at CNN, but Kathy Griffin recently also got jettisoned.
Apparently there are limits, even at CNN. I was about to say we don't know how far "too far" is at MSNBC, but even they booted Olbermann back in 2011.
Blazing Cat Fur: Cannibal Reza Aslan fired from CNN
Daily Mail: CNN drops Reza Aslan after Tweet
Daily Wire: Flashback Reza Aslan
AoSHQ: CNN drops Reza Aslan
TOM: Transgender Advice