That seems blatantly false to me. The Assad regime is certainly guilty of all the things on your list, but ISIS are also murdering and torturing people by the tens of thousands and systematically exterminating entire groups of people (has everyone already forgotten about the Yazidis, if nothing else?). Insofar as differences in scale exist, they seem to exist only because ISIS doesn't have the capacity to kill as many people as they'd like. Both groups have institutionalized horrific violence as a matter of policy.