There's a lot that fits between automated tests and code review. We have an extensive system of static analysis and code quality bots that run, but there's still a lot of design patterning and higher level functionality that machines (or, at least, our machines) don't always catch.

Obviously, it depends widely on the codebase and the number/quality of engineers working on code, but it's been my experience that a team reviewing each other's code is still something that can't be 100% replaced with automated tests.