I love code-reviews. With the right people, they can be useful both to achieve high-standards of code quality and also improve your own engineering process. The requirements are quite high, I think you need some combination of the following:

1. Both reviewer and reviewee are focusing on getting the best outcome possible, in good faith and with generosity.

2. The reviewer concedes that there can be equally valid approaches to a given problem or taste wrt. aesthetics. They do not try to gratuitously force their style upon the reviewee. The reciprocal must hold as well.

3.The reviewer makes practical suggestions and ideally accompany their comments with snippets of code. They involve themselves into being part of the solution.

4. The reviewer focuses on the substance of the pull request. That means putting in the time to understand the real logic, putting themselves in the shoes of the reviewee (with their help), and trying to challenge it so that the limitations of the approach are known and documented.

5. The reviewee makes an effort at slicing their request into readable and compact sub-PRs if needed. Similarly, the reviewer makes a best-effort attempt at starting their review within a reasonable time.

Those are central aspects of a productive engineering culture anyway. You only need to find someone else that shares those "values" (i.e focusing on the best outcome possible as a sort of devotion to Engineering - so to speak) to grow this attitude within your company.