You are picking the least important detail of the story. The deal is, Google found a simple way to kill the performance of a rival browser... so they exploited it and immediately started advertising how slow the rival was. By the time the rival fixed the performance issue, the damage was done. If true, that's pretty dirty, and it directly contributed to the growing browser monoculture.
This is a wild conjecture. Whatever happened to innocent until proven guilty? The fact they jumped on it means that someone was paying attention to these metrics, but assuming chrome has any influence on YouTube is laughable.
