It's more about the size of the task I try to do, it's quite possible to get opus4.6 to one shot a "good" 30k loc change with the right planing doc. I'm not confident I could get similar results handholding. I also tend to want to know the major decisions and details in such a change up front rather than discovering them post-hoc.
This could simply be a matter of style however.
One-shotting 30k LOC is no use to me because none of my colleagues will review a PR that big. But more to the point, I wouldn't be able to review it either, and I think we're still at a point where you do want to look carefully at the output these tools generate.