Mahayana view on why Theravada's anatta is insufficient to uproot ignorance?

A Mahayana-practising member wrote this comment : > With respect, the Theravada generally has a much more coarse > understanding of emptiness and anatta and is confused as to the object > of negation. In much the way that placing a bag of ice on a gushing > head wound has some efficacy, yet is utterly incapable of actually > curing the wound the Theravada understanding anatta doctrine is very > helpful, but insufficient to provide a genuine antidote to ignorance > and hence suffering ..... The Mahayana tenet systems ... > believe Theravada adherents are not ready to understand, > but will understand the selflessness of phenomena eventually as they > continue to progress on the path. I would like to understand the perspective of Mahayana Buddhists on why Theravada's anatta (and dependent origination) doctrine is "*insufficient to provide a genuine antidote to ignorance and hence suffering*" compared to Mahayana's sunyata (emptiness) doctrine?