Worse, soon he will be their manager and then those failures and missed golives will be his fault.

Only if the Peter Principal is in effect. As a manager they would be uniquely positioned to scope and assess the prep work. With a bit of mentoring they might "get it" sooner, rather than "eventually".

It's not that they don't get it, it's that they don't care.

Not for this paycheck :)

I've been a manager in earlier times and got shit from all sides. Nearly drove me to a burnout. Paycheck was still horrible. So i quit that.

That would make a fun conversation with the CEO :)

I have a coworker that placed a "return true" at the beginning of a failing test, and when I reverted the change spent ONE ENTIRE MONTH arguing that I had broken the test and it was now my responsibility to fix it. Several emails per day, because according to him what he did is completely legit.

He was at my same level then. Now he's 2 levels higher.

Sounds like they already are.