They do. It's already like this with business recommendations, always use a personal reference before anything else.
I've thought about making some digital reputation system that cannot be gamed. You can rep people you know and then query if there's any path of rep from you to a random person. The global number of reps you have doesn't matter, only paths. Problem is this only works if the target person can't tell that you repped them, which is impossible to hide because they can just rep you with a fake account then see if there's a path to their real account. But maybe with some fuzzing.
I've thought about making some digital reputation system that cannot be gamed. You can rep people you know and then query if there's any path of rep from you to a random person. The global number of reps you have doesn't matter, only paths. Problem is this only works if the target person can't tell that you repped them, which is impossible to hide because they can just rep you with a fake account then see if there's a path to their real account. But maybe with some fuzzing.