(There are workplaces where that's the norm, I know -- it tends to be a thing with smaller teams with codebases that everyone understands fully, and much less a thing with larger teams where different people have areas of the code they understand more than others.)
With AI code, though, it's _your code_ and you can't give it a lgtm, you actually need to dig at it until you do fully understand it, fully agree with it, and could justify it to a hostile reviewer. It's a different level of rigor.
Not all engineers apply that rigor, though, which becomes a problem.