1) capitalism and the money is all you need has gradually worn down all other moral and ethical institutions over the decades. Without something like WWII to reset a popular ethos in a uniform manner, it's a gradual slide downward
2) maybe the universality of team sports in the United States, where again winning is all that matters and if you aren't bending the rules and burdening the referees, you aren't trying.
3) this all gets cranked up based on socioeconomic stress, which also is being steadily ratcheted up each decade.
I guess it depends on what you mean by contentious and by whom. The current US administration is a love letter to grifters, con artists, liars, and cheaters. And is staffed with many of the same kind of people.
It's a fairly long way from those people elected to the actions of individuals.
Given a few minutes of thought, it's not hard to imagine one side calling the other cheaters, while holding themselves to higher standards (even holding up those "others" as reasons why its important to be honest). That's just how politics seems to go.
I was thinking more of our cultural appreciation for con men, Robin Hood types, and so on. Many movies come to mind over the past several decades; Ocean’s Eleven, whatever that grass seed salesman movie was, etc. Also, I’d been considering the endless cheating in multiplayer games, whether video or IRL, for as long as humans have played games; and the tendency of United States drivers to cut in line in congested traffic, which is a less-considered form of cheating but still hits all the right points to count as such. Olympians and their endless doping scandals demonstrate that some authorities might think cheating is wrong, but athletes clearly aren’t so uniformly concerned about it. Still, you make a good point about politics demonstrating both the controversy and popularity with voters of cheating and grifting!
Those movies, stories, and games are popular _because_ we have an aversion to rule breaking, IMHO. The average person could never muster up the courage to steal a candy bar, let alone a treasure from a kingdom. It's a fun fantasy to live out precisely because we cannot bring ourselves to do it in the real world, and precisely because it wouldn't go well in the real world.
Being asocial myself, the aversion described comes across as an outcome of societal pressures, rather than any sort of innate characteristic. I still voluntarily adhere to the principles intended by it, but without ever feeling the aversion that typical vulnerability to social pressures confers. So, yes, I do agree that aversion holds true in some social environments — but not all. If one constructs a theoretical culture where lying to, conning, and stealing from outsiders is ethically neutral, then the opposite becomes true: courage is only required to steal a candy bar from an insider, else it’s ethically neutral and courage is not required. This isn’t a thought experiment; such cultures do exist within the United States and have numerous adherents both in U.S. politics and at home. One of the controversies around cheating on homework is whether it’s cheating or not; if a degree ultimately earned fraudulently is only used to exploit outsiders — e.g. including faceless corporate and government non-person entities — then it is not necessarily cheating under an “insiders-only” ethical framework at all. The threats of such frameworks are many and various, but right at the top of the list is “ethical concerns are only applicable to in-group members”, which neatly sidesteps the courage otherwise required to take advantage of a professor, college, etc. Thus the controversy: to say that “cheating is wrong” assumes not only that cheating is “wrong”, but that the ethical concerns implied by the label “cheating” are even applicable at all. Unfortunately, colleges tend not to engage at that level with students (other than those that self-select into philosophy!), and so punitive-only efforts are ineffective at shifting the underlying cultural issues.
