I've worked at various enterprise-scale companies over the past 2 decades, and this has been my observation too. As you say, there are exceptions, but a lot of

I've worked at various enterprise-scale companies over the past 2 decades, and this has been my observation too. As you say, there are exceptions, but a lot of managers are there because they've "played the game" well - they're good at networking, know the right people, say the right things at the right times, and when they think it will help them, they don't hesitate to throw other people under a bus.