Things move pretty fast in Trumpland, it seems to me that Pottinger’s influence has only grown since the events described in Bolton’s book (which we will take for granted are true though I certainly don’t feel that is likely). Most of the stuff they have done recently that has any nuance seems to come from him. So I don’t see any reason he would step down from that perspective. As far as “conscionable”, I think for people who care about such things the damage is done when you start working for Trump, not when you quit or get fired.