Its rare that devs are on standby, waiting for a pr to review. Usually they are working on their own pr, are in meetings, have focus time.

We talked a lot about the costs of context switches so its reasonable to finish your work before switching to the review.

People are busy, and small bugfixes are usually not that critical. If you make everyone drop everything to review everything, that is much more dysfunctional.

Hehe I'm waiting right now, should have been reviewed yesterday but I'm like alright, I'll just chill then.

nobody will immediately jump on your code review

Sure, but five hours is a lot of time, and a small fix takes little to review.

So, 1 hour? Sure. Two hours? Ok. But five hours means you only look at your teammates code once a day.

It's ok for a process where you work on something for a week and then come back for reviews but then it's silly to complain about overhead.