Human developers don't produce code at such a rate, and their judgment is, on average, better. So one, the review doesn't make you feel like you're slowing things down much, and two, the problems are less hidden.
I can only presume you work with talented people somewhere that is not representative of most companies. You're definitely overestimating the average programmer's abilities.
The other is using Agents as critical reviewers. I've let Opus 4.7 review PRs by very senior people. Most of the suggestions are meh, but usually there's at least 1 or 2 that improve the code base unequivocally.