That is exactly why judgement should have been deferred. In the face of uncertainty, given the situation, withholding comment or querying neutrally would have been optimal. That is clear with foresight, not just obvious from hindsight. I did not see that thread the first time but it is the tone and not the words that would be so damaging.
Man up. Very likely he had already internalized the blame for his current state. Such statements would be seen only as confirmations of his weakness and foolishness. Criticisms would be isolating and over-weighted . For someone so prodigious it would have been especially difficult.
The risk from destabilizing a person genuinely going through very difficult external and or internal moments, even if they proportion fewer, far outcosts the risk of building a careless individual's misplaced ego by giving them attention in the form of neutral to supportive questions. Yes it will take a bit more effort to not follow all "I made a mistake" with "man up and learn from it" but I think we would all be better from it. Especially those at the extreme end where manning up requires prefixing with super.
I dare say I envy those whose paths through life is such that a phrase like that enters an initial treatment of someone facing any adversity. That they have never sensed helplessness so vast, it opens a vortex to the place of lost souls, washing away the vivid colors the manned-up paint with while slowly dimming any ability to answer the on appearance hopeless question of What now? Nothing of course.. ?