I've talked with professors at a major US research university. For Master's students, they are all paying a lot of money to get a credential. That's the transaction. They don't really care about cheating as long as they go through the motions of completing the assigned work. It's just a given, and like you say it takes more time than they have to go through the acacdemic dishonesty process for all the students who are getting outside help or (now) using AI.