I see it as estimating a project vs estimating individual tasks. The former is a business need. The latter is not. After some high level analysis and decompos

I see it as estimating a project vs estimating individual tasks. The former is a business need. The latter is not. After some high level analysis and decomposition, I can say a project will take 3 months. But there’s no need to spell out every minor widget or method with hours. And this is separate from any t-shirt sizing a team does internally to plan their own time. This should be strictly internal and used as much to generate design discussion as anything else.