Actually there’s some pretty good evidence that Assad is indeed an evil dictator. His family has been in power for a long time despite coming from a minority group in Syria, which almost always requires significant repression. His father had a history of extreme violence against dissidents, and Assad appears to have exhibited some of the same early in the conflict (when a somewhat credible peaceful opposition and a semblance of a journalistic presence both still existed in Syria). And most importantly, as your article acknowledges, he has undoubtedly bombed cities (his own, as it happens) to rubble. Who cares why? It can’t be excused as self-defense:the possibility of a genocide against his well-armed sect is remote.
The problem with this uncertainty-wash is that it causes you to miss a chance to make the much truer and more generally applicable point that even evil dictators are almost never worth trying to remove by force. Genocide and territorial aggression are the only things that may make it worth trying.