Earlier quoted context omitted.
There are two lines of evidence: first regarding his cheating online, which is easier to do and easier to check. Chess.com banned Hans and put out a statement saying that Hans cheated more often and more seriously than he claimed. [1] The second line of inquiry is statistical analyses of Hans's over-the-board games. See my original comment for one such analysis, but he really has been playing at an absurd level in so…
What a person did at 16 years old is hardly relevant now, and it is definitely immoral to keep bringing it up without new evidence. How long would it take for people like you to stop bringing up 'he has a history of cheating'? 10 years? 20 years? 30 years? 50 years? He had played at a way more serious events, and still the only 'evidence' of cheating is his relatively good performance. Until someone comes up with an…
That argument works better when someone's 25 than when they're 19. This isn't the distant past, this is 3 years ago. That's definitely recent enough to be a black mark on his reputation. On the other side, the main person who's suspicious of them isn't some internet random. It's the world greatest chess player, which should is decidedly a mark in one's favor reputation-wise.
This is the very basis of how reputation works. You slowly establish reputation by having a track record of positive behavior, you rapidly tarnish reputation by having a track record of negative behavior, and when you are making judgements based on limited information about the activity at hand, you trust the more trustworthy.
Think of how much good will Microsoft has had to build in the last 10 years to try and make up for the 20 before that. Think of the fable of the boy who cried wolf. Trusting those who have earned it and distrusting those who have wronged before is basic society 101.