Maybe I'm saying that I reject the assumption that off-screen cheating is as effective as people think it is. (I really don't have any statistics for this, though -- does anyone? I'm just making my own assumption that it's not having a hugely noticeable impact on the overall pool of hired coders.)
Either way, I can totally see why you'd be mad cheating exists. But maybe take some heart from the fact that employers don't like it either, and will be on the look-out for it? I mean, if you preemptively remove yourself from interviewing because "What's the point if there's cheaters out there" - it becomes a self-fulfilling prophecy.
there are people that are entirely clueless and then there are people that are solid engineers who aren't willing to spend months prepping by leetcoding. there are plenty who can cheat, and still do fine day to day once hired.
either way, even if the people that cheated don't have enough skill to keep the job, they've already taken that job and pushed out someone else that's legitimate. then they have to pip them, fire them, and reopen that role. that's months wasted and the original qualified candidate is long gone.