My experience is that Google code reviews tend on the whole to get so caught up in stylistic and micro-level technical comments that overall design gets lost in the shuffle. Especially in something really large and old and evolved like Android or Chromium.

In general the code review process can work at Google for most projects because the essential design questions are already set in stone. You use protobuf/gRPC, follow the patterns that other services have mandated. There is usually a "recipe."

And within Google design problems are perhaps sometimes addressed during PRD/design-doc phase, in a big Google Doc. But not always.

But I can see how this could completely fall over when these things go out into the external world.

That and the need to make everything into small microlevel reviews that get nitpicked for days means that large wholesale architecture simplifications and refactors just don't really happen very often. Few projects have people with that kind of authority.

The Torvalds review is pretty savage.