As soon as one person becomes more important than the team, as in the team starts to be structured around said person instead of with the person, that person should be replaced. Because otherwise, the team will not be functioning properly without the "star player" nor is the team more the sum of its members anymore...
The example of Steve Jobs used in the above post is probably a prime example - Apple just wouldn’t be the company it is today without that period of his singular vision and drive.
Of course they struggled after losing him, but the current version of Apple that has lived with Jobs and lost him is probably better than the hypothetical version of Apple where he never returned.
Great teams are important, but great teams plus great leadership is better.