What happens if:
1. Bob is more or less responsible for a big chunk of the kernel, e.g. the scheduler.
2. Torvalds knows Bob, and knows that Bob is employed by Redhat to work on the scheduler.
3. Alice writes a new improved scheduler which has the potential to replace the old one.
Now, how does Torvalds react? It would be hard to tell Bob that he’s no longer in charge of the scheduler. Bob’s job might be on the line – why would Redhat keep paying Bob if he suddenly had a lot less work to do? Maybe Torvalds met Bob a few times and had a beer with him, making it even harder to replace his work because it becomes personal. Torvalds could harm Bob’s career.
Surely this makes it hard to become a big new contributor? All the existing contributors already know each other and they won’t want to dump eachother’s work.