I've found that engineers on a large team do read every line, mainly due to the fact that the skill levels run the gamut from intern to lead, and only 1 or 2 people out of 12 might have knowledge of the application being modified.

It's actually getting worse due to "AI code bloat", for example I have 16k lines of code to review across 3 apps by the end of this week. Normally it would be a quarter of that, but what Claude produces is extremely verbose in some places and anemic in others, and I can't tell at a glance what's right and what looks right with that much ground to cover.