Imagine a world without Printz. Congress could just commandeer local police into assisting ICE, assuming that Congress was willing to pay the political price for doing that. Or they could delegate some limited power to the President to do the same thing. In those circumstances, federalization of the National Guard would only be needed if the combination of local police and ICE were unable to enforce the law, restore order, etc.
Thus, you could say that an unintended consequence of Printz was to increase the probability that the National Guard or regular military forces would be used by the President within the United States.