If his CEO friend didn't know he was doing this, they would not be acting together - the friend would not be performing any action at all. But if they communicated with each other and agreed to act this way (like Apple and Google did), then it would be collusion.

But even if it wasn't outright collusion, it could still be ethically questionable to limit another person's opportunities just because you're afraid of losing someone's friendship.

It may be colluding, but the comment said it wasn't "about" colluding, which may also be true.