Whether Hans cheated OtB is not really the main issue although most commenters get hung up on it.
Occam’s Razor suggests we should strongly believe he didn’t cheat OTB.
The bigger issue is that known cheaters create a cloud of suspicion that puts their opponents at a huge disadvantage. Magnus has spoken about this before - if you think someone might be cheating you can’t concentrate on chess.
This suspicion can be allayed with extra security but that extra security was only deployed after Magnus left.
Occam’s Razor suggests we should strongly believe he didn’t cheat OTB.
The bigger issue is that known cheaters create a cloud of suspicion that puts their opponents at a huge disadvantage. Magnus has spoken about this before - if you think someone might be cheating you can’t concentrate on chess.
This suspicion can be allayed with extra security but that extra security was only deployed after Magnus left.