I think you’ve missed what the sin was, as well as the context of the players.

The sin was not the bad code. Let me say it one more time for clarity: the issue was not the code

The issue was that, when presented with the defect (inevitable outcome of any software project: not intrinsically sinful) Mauro started blaming other people on a public mailing list

Mauro, being a maintainer, was in a position of authority. Like a police officer, their bad behaviour reflected poorly on the organization*as a whole.

If a cop was abusing their power (publicly or not), I expect the chief of police to come down on that abuser; to make clear that this abuse is absolutely unacceptable, not only within the accute instance, but within the greater context of the expectation of the behaviour of the whole organization.

Mauro chose the context of his abusive behaviour as the public mailing list.

Him getting slapped down in that same forum is the direct result of his own choices.

In the same way that I would be upset with the chief of police not publicly and harshy denouncing an abusive police officer, so would I be upset with the absence of such a response in this situation