Premise: "Corporations can cause harm" Premise: "Corporations shouldn't cause harm" + Milton Friedman + Deregulation Advocacy = DOES NOT COMPUTE.
If we agree that corporations can harm, but shouldn't, then it follows that a corporation's actions must be regulated somehow. The primary options are self-regulation (to avoid doing harm, a corporation voluntarily forgoes a profitable activity) and external regulation (there are rules, enforced by the state, that limit or prohibit some kinds of profitable activity). If, as Friedman argues, CEOs should abstain from self-regulation, then external regulation is required if harm is to be avoided.
I suppose in reality, we have both - there is some self-control from even the worst CEO (there are no too many massacres), and there is plenty of regulation. I suppose those that advocate simultaneously for deregulation and market freedom would agree with the principle here, but take issue with the amount and nature of the external regulations.