The American people feel that they have been stolen from at this point in history - with considerable justification. These kinds of remarks will do nothing to motivate the indolent who need a kick in the butt, but they might offend those who are actually trying and not succeeding.
In the Reagan era it was OK and justifiable to say this kind of thing - today, in the Goldman Sachs era, it is imperative not to come off like you are blaming the victims while banksters loot the system. So Cruz is being tone deaf, here.