This is because we have recently transitioned out of a society in which for centuries Men and Women have been socially segregated except for specially designed courtship situations, and homosexual relationships have been condemned. When you eliminate these boundaries after centuries of living within them, men and women subconsciously assume that any interaction is a possible sexual interaction, and this leads to cheating. I think it's a very good thing that those taboos have been eliminated. But now that they are gone, that leaves it up to the willpower of each individual to remain faithful to their sexual commitments and agreements. This isn't easy. That's probably why these taboos were set up in the first place. But it's doable. A "heightened likelihood" is not an inevitability. Unless we are going to take women out of the work pace again, it's a skill we are all going to have to cultivate in this new modern world.