Ah, yes, the panacea for all mental health problems: brushing them under the rug and not talking about them.
His mental health wasn’t relevant to the attack from any report I’ve read. That makes it a bit odd and more than a little thoughtless to highlight it.
People slow down on projects for a ton of reasons. The guy could have been in chemo or had a kid. The result would be the same: he’d need a co-maintainer to keep the pace. The attackers would’ve capitalized on that. They’d plainly been waiting for whatever opportunity would work.