It cannot be the only effect, since this pen-and-paper effect manifests itself in other places: when you kook at old industrial systems' plans (nuclear power plant in the example I have in mind) you're very surprised to see how small the number of revision is for the plans: because it's very tedious to re-do the entire plan from scratch by hand, people used to be extremely cautious when design them. Today with CAD software, revisions are cheap and producing half backed plans that need later correction is the norm.

Maybe the new way of doing thing is still more efficient in the end, but maybe not.