If a manager says they provided oversight of their developer employees, and the code was not as good as the manager thought, would you say "the manager has had their brain broken by the existence of employees"?
This manager is directly providing an unrelated team with an unprompted 150-file giant PR dumped at once with no previous discussion. Upon questioning, he says the code has been written by an outside contractor he personally chose.
No one has onboarded this contractor to the team, and checking their online presence shows lots of media appearances, but not a single production project in their CV, much less long time maintenance.
A cursory glance at the files reveals that the code contains copypasted code from stackoverflow to the point that the original author's name is still pasted in comments. The manager can not justify this, but doesn't seem bothered by the fact, and insists that the contractors are amazing because he's been following them in social networks and is infatuated with their media there.
Furthermore, you check the manager's history in slack and you see 15 threads of him doing the same for other teams. The ones that have agreed to review their PRs have closed them for being senseless.
How would you be interacting with this guy?
That could be either regular incompetence or a "broken brain." It's more towards latter if the manager had no clue about what was going on, even after having it explained to him.
This guy is equivalent to a manager who hired two bozos to do a job, but insisted it was good because he had them check each other's work and what they made didn't immediately fall down.