I think that's only one subset of cheaters, many people use cheats in non-pvp games or use cheats in a specific server where everyone has the same cheats. It's often just a way to get more replayability out of a game someone really enjoys.

In monster hunter, the speedrunning community is migrating to PC because the ability to use cheats to negate the huge amount of RNG present in the game. Cheating is usually looked down on by speedrunners for obvious reasons but because of the difficulty of speedrunning a game with so much RNG(not rng that effects your gameplay, but that effects your ability to play at all), modders are basically making a new game with the rng removed and people are speedrunning that, and it's widely accepted as necessary by the community.

So cheating is often just a means of either getting something new out of a game or 'fixing' aspects of a game that the community takes issue with.

I agree that players like you describe, who's main goal is griefing other players, also make up a large portion of cheaters, just wanted to further elaborate on your response that not all cheaters are doing it to 'move up the leaderboard'