I mean, cheating is likely to be an actual problem. Not that it justifies the malware, but there is a real problem even if that's not a reasonable solution.
It's not a question of if it's a problem. People do cheat, and that is a problem. It's a question of how much of a problem it is. What percentage of games have cheaters in them? I would bet there are several orders of magnitude difference between that number, and the percentage of games where someone cries cheater.