Yeah for sure, when i was a kid i always activated cheats for Doom 1993
I also always cheat in Bethesda games because the console command in those games is really fucking enjoyable lol, i always mess around with it, its not cheat because game is hard but cheat because its fun, you can set a scale to make your character taller, you can fast travel from anywhere in case you get bugged, you can mess around with NPC a.i, its really hilarious and if you need gold or items you can spawn them instantly, its just a very convenient and useful system.
I also cheated in my first playthrough in System Shock 2 a lot of years ago, the cheat i used was to make me have chemicals because i was lazy to backtrack and lose ammo on respawning enemies lol
I also cheated in roguelike games, some of them, when i wanted to have more gold in a single run so i used cheat engine to buy everything, kekekeke its fun to cheat in this genre.
But all these cheats are rather for the fun factor and not to beat the game.
I only cheated 2 games to beat and those are:
1- Pathologic 2
This game was a nightmare, so i had to cheat, at some point i was getting suffocated, its a tough time and i wanted to see as much as possible from the story so i went out of my way to cheat. This is the biggest cheat i have ever done in a game.
And no i didnt mess around with the sliders, I even used the console system LOL
2- Commandos 1
The old school commandos games were super challenging for me because i played them when i was a kid, i literally was in the 4th grade when i started playing this series and for a 4th grader those games are super hard, so my cousin would come and help me finish levels but at some point he got tired of me demanding that and gave me cheats, i started using them and you know kids! i found a way to exploit it and have fun shitting on everyone so i went with it and started cheating levels, eventually i beat the game with no effort. 2 years later i played the sequel without cheats and it paid off and now i consider it my favorite game of the series, but it took me months to complete lol.
Thats it
Edit: So OP is asking about Online games, sorry i missed that.
I never cheated in Online games, i always played fairly, although i remember trying to find cheats for Runescape lol, i wanted to get more gold and there was no cheat so eventually i grinded for it. But in any skill based game cheating is not worthwhile, so i never cheated in Counter-Strike, League of Legends, Street Fighter or basically any competitive game.