Comment by alphazard

Code review should really only exist to guide contributors to the owner of the code they are changing. A new contributor shouldn't need to know the team structure and history of the organization to get changes in. That should be solved by the tooling. Do whatever you want, and the tools will force you to bump into the right people before you can merge.

It's very strange that most companies (maybe GitHub is to blame for this) have something like a free-for-all where anyone can approve anything, as long as they themselves aren't the author. As other comments have mentioned, this reliably creates reviewer cliques as engineers seek out the path of least resistance to get changes in. Those who haven't figured out the game often lose hours of their time to nitpickers and pedants without anything better to do.

This also results in a slow decay since most of the code ends up being written by people who are good at getting code merged, and not people who are good at building the software.