In my experience a culture where teammates prioritise review times (both by checking on updates in GH a few times a day, and by splitting changes agressively into smaller patches) is reflected in much faster overall progress time. It's definitely a culture thing, there's nothing technically or organisationally difficult about implementing it, it just requires people working together considering team velocity more important than personal velocity.
Let's say a teammate is writing code to do geometric projection of streets and roads onto live video. Another teammate is writing code to do automated drone pursuit of cars. Let's say I'm over here writing auth code, making sure I'm modeling all the branches which might occur in some order.
To what degree do we expect intellectual peerage from someone just glancing into this problem because of a PR? I would expect that to be the proper intellectual peer of someone studying the problem, it's quite reasonable to basically double your efforts.