Code review doesn’t catch bugs. Sure, sometimes an experienced dev can spot a bounds error or race condition, but CRS are for knowledge sharing and style adherence.
Beyond the "this will likely deadlock without a timeout", "this does not clean up after itself on exception", "if the cache is not hot, this operation you assume is 1 sec will take 1 min" type thing — one of the strongest points of code review is having a conversation about "this code is hard to understand" and turning code that's correct if you think about it really hard into obviously correct code.
It takes a reasonably strong reviewer to get there though, and that's not always possible.
It can but it's definitely not a 100% surety (as some people seem to think.)