I find it very strange that non-conformist Jobs who hated 1984ish IBM would be pro-uniform. It's a good story in the overload of Jobsian mythology. It shows a different side of him - that he worried about culture in addition to product, that he wasn't always consistent, and that even He could make design mistakes. Much more human a story than the usual fluff.
It shows are more interesting transition from Jobs and early Apple wanting to own the PC business, to Jobs wanting to own the "2%" marketshare with really beautiful, well-designed products.
I think the motivation was always there for beauty, but it wasn't until Windows 3 was introduced and successful (and the Mac was overpriced to $2500 by Sculley) that Apple could really accept that they weren't going to have it all, marketshare and creative focus. Fortunately for everyone they settled on the latter.