Junior engineers often think that code review is about identifying and fixing bugs before they hit production. This is not the primary benefit of a healthy code review culture. Instead, code review is critical to promote collaboration and knowledge sharing among team members.
Engineers can learn from each other's code and improve their own coding skills by seeing how their teammates approach problems. For engineers, leaving comments (or memes) on code is an ideal avenue to build culture and socialize.
Focusing solely on finding bugs during code review can be counterproductive. If you're only looking for bugs, you may miss other important aspects of the code, such as maintainability, readability, and performance.
Finally, bugs are often better caught through automated testing or other processes -- humans are not very good at this!