I think that May is too awkward and unpracticed to genuinely sell her ideology to the public, whereas Cameron’s ‘charisma’ and polish meant he could sell dangerous ideas in a palatable way. Even many people who are nominally opposed to austerity still retain the underlying ‘rationale’ for it when it’s not really accurate, which I think will have a toxic effect on political rhetoric for years to come.
Austerity, his anti-refugee rhetoric and calling the fucking EU referendum (plus encouraging Euroscepticism during EU reform negotiations) are far more influential than anything May has done, or really can do without a majority, IMHO. The hideous things she did as Home Sec must have been okayed by Cameron, and whatever she does in regard to Brexit wouldn’t have happened at all if Davey Cameron hadn’t been such a pie.