There are schools with severe penalties for cheating (Army/Navy, Haverford, Davidson), but most aren't set up for that. Professors didn't self-select to be prosecutors, and we didn't spend decades becoming world experts to then become cops.

Love the sinner, hate the sin. If you let yourself start blaming students, you open a pretty corrosive path of moral judgement. Students are clever, and they're making choices informed by what they see in the world. Don't blame them for being unwilling to fail a class that cost a down payment on a house. Don't blame them for seeing powerful people get away with cheating and trying to do the same.

Kallus is right: qualitative assessment is an adversarial problem. Build the assessment correctly, and all of those previous points become moot. By clearly establishing and enforcing the rules you make it more fair to boot.