I find it troubling that so many self-professed "professionals" on here are tiptoeing around the F/O's documented history of mental illness and a system that allows such a person with that history person to hold a medical certificate of a class sufficient for a commercial pilot certificate to remain valid. Sorry (not) if that sounds "discriminatory" but in aviation, particularly for those involved in commercial/common carriage of passengers with no say who occupies the front seats, our whole careers are discriminatory in terms of performance and health standards that must be met.
But it seems some would rather co-opt this event as a vehicle to bray about their pet aviation peeves like pay, their opinions on what they view as "senseless rules" etc or further conspiracy theories. More incredibly, some view this as a fraternal issue in spite of the fact we know the altitude preselect was purposely set lower, that A/P entries must be made in order to begin a descent, and disabling the door entry keypad from inside the cockpit takes a deliberate act that requires operating a guarded switch.
If these things were done, I want no fraternal association with that person, mentally ill or not, who betrayed that trust and perpetrated this horrible event. 150 innocent people died folks, the secondary issues and "woe is me I'm an underpaid pilot" are irrelevant and somewhat disgusting.