Should we stop using the simplistic argument that we shouldn't have a law because criminals will just do it anyway?
No. A good set of laws designed to make society safe and otherwise desirable to live in is a good idea, and we should cheerfully submit to them as a part of the social contract.
However, if the social contract is broken and there are no consequences to the scofflaws, as when several people brazenly defy lawful subpoenas and they are allowed to do so, there is no longer a contract or a duty to obey the laws. Before that, one should not run a red light, for example, even if one is stopped at the intersection and can see clearly that proceeding on red would be safe. One waits anyway as part of that social contract and a respect for the law.
But once that contract is broken, there is no longer any duty to respect those laws, and they can be broken whenever one feels it is safe and advantageous to do so. We still don't run red lights if there is a real risk of an accident or a ticket, but not at any other time..
I realize that many will disagree here and say that one should still obey the law even if others are allowed to break it without consequence, but all I can say to them is that for me to participate cheerfully and willingly, I need to see a just system. I don't need for everybody to obey the law in order to obey it myself willingly, but I do need to know that those who get caught violating it will be penalized. If not, I lose interest in cooperating.