The nextspace screenshot shows apps and icons with very bright colors. Nowadays icons and apps tend to be colorful, and since they follow different color schemes, a collection of them has a high probability of clashing (e.g. the gray Gimp next to the orange Firefox.)

Nextstep could maintain a consistent aesthetic, I think, because: 1) there were not many apps available on it as there are now on nextspace, and 2) a single company, which had a notoriously style conscious CEO, produced these apps. Nowadays, apps are produced by different groups, with different tastes (let alone skills) in designs.

Nextspace faces the problem of maintaining the muted and clean style of nextstep, in a more diversified world. That's what I was reacting to.