Humans seem to be evolutionarily predisposed towards interest in what other people are doing, since this has allowed for the social cohesion that’s been instrumental to our survival. There is also an element that, the more other people there are who care what a particular person says and does, the more people will care what that particular person says and does, creating a positive feedback loop. Social status in the form of notability must have developed as a way of attaining reproductive access.
When a mob boss tells three of his underlings to commit a murder, and then the three underlings commit the murder, is the mob boss culpable? Most people would say yes, even though he himself did not commit the murder, because he is the boss. But isn’t it possible for the three underlings to have just ignored the bosses orders and done nothing, in which case he would have just been talking? No, most people would say, because the underlings did commit the murder and they have entered into a hierarchical relationship with the boss where they are obligated to follow his orders.