The Bairstow stuff is appalling.
On a human level, IMO, actually much WORSE than the calculated cheating, through the shenanigans with the sandpaper.
The Aussie PM has come out and stated that it 'beggars belief' that sportsmen would cheat in that manner. But it really doesn't. It beggars belief that they could be so stupid, but not that they might be minded to cheat. Cheating goes on in some way or other in almost all professional sports, so we know that it's in the psyche of some competitors to take that path - to weigh up the act against the potential reward, and decide its worth it.
On the other hand, to stand there in the field, yards from a fellow young professional, and to taunt him about the suicide of his father (another fellow professional cricketer, who JB himself discovered hanged, on his return from school, at the age of eight), purely in an attempt to break his concentration in a sporting contest? THAT, to me, genuinely does beggar belief.
Did that actually happen? Not doubting you, but I must admit to losing interest in the Ashes very early so I didn't read all the reports. However if that's true ..... well, it would be bad enough behaviour in an interrogation cell, but in a sporting environment, like you say it beggars belief.
EDIT: Reading some other posts after yours it seems others are just hearing this too, but that it has never been 'officially' discussed.