PRs & Code reviews are a blocker and bottle-neck for value generation. Allow me to explain.
A Pull-request was a feature created to allow maintainers of an open source project to receive changes from unknown contributors. It solves a trust problem, allowing the maintainer to review code before rejecting or accepting changes.
Developers working together as part of a team don't have trust issues. Otherwise, it is a different problem in which PRs are not the solution. At best, the issues of a team are about quality and norms.
Automating testing and practices like TDD, CI, and CD can solve quality problems. Automated tests create faster feedback loops when compared to a PR waiting for review and the usual back & forth with comments.
Testing Driven Development helps developers to design their code better and enable testability. Tests are created to support the acceptance criteria in the stories. When they all pass, developers are free to merge the code and move to the next story.
Continuous Integration reduces the chances of merge conflicts. It supports the idea that any code in the main branch is working software ready to ship to production. Pipelines produce feedback and help to avoid regressions.
Continuous Delivery accelerates teams by avoiding branch strategies. Everything is merged into the main branch and continuos tested. Code is deployed into production often, and feature flags can be used to allow for tests in production or canary releases
Pair Programming or Mob Programming eliminates the need for code reviews. Code is reviewed as it is produced. Disagreements can be solved on the spot instead of async through comments. Knowledge is shared, avoiding silos.
Norms can be enforced with code static analysis tools as part of the pipeline and pre-commit hooks. Quality gates can be added to implement minimum thresholds. Developers can focus on value generation rather than reviewing code that is faulty in style but functionally correct
For regulated markets, compliance and regulations can be satisfied without code reviews in most cases with modern Quality practices.
Unless you are developing an open source project, you should seek to stop doing PRs & Code Reviews. It will accelerate time-to-market and help to improve the product further with more frequent customer feedback.