This might sound rough but the lesson should be "don't be an idiot".

Time for shouting "king's naked!" comes eventually but people who ignore timing will end up losing this game. The secret to this is to understand how other decision-makers see the status quo. Who made a bet on this person? Who understands that he is THE problem? Is right now the best time for a direct opposition?

And sometimes it's just easier to accept that it may make sense to work elsewhere.

Hard agree. But yet, what became of the one who did try to fix it?

He left that shitty place early and lived happily ever after?

I learned how big companies function and how to get ahead quick. The two things - politics and competence are not mutually exclusive.

I had one project where there were about 10 people working on it. Shipped about 10k units. Doing decent but not hockey stick money. Until we hired one guy. We went from a 10 man team to 2. He could not get along with any one. No one could approach his amazingness. He would triangulate people and get them kicked out of the group. Soon those 10k units and 5 customers were getting rather pissed off as nothing was getting done other than giant presentations. He really wanted to be a manager in 6 months.

Before he could infect another group with his special touch I politically maneuvered him into the most boring of tasks that no one wanted to do. He had run the one project into the ground. At the right moment I used his own triangulation manipulation bits on him. I had to become that which I despised to basically take him out before he did too much damage. I had him shunted off to a task that if it was done no one cared. It was a pity too as he was a competent programmer. But had too much of an ego to listen to the other decent programmers around him.

Moral of that story? There are jerks out there that will take out a well functioning team and not even see they are doing it. Beware of them. The world is not broken. But there are those who start fires because they like to make messes.