Honestly, while it’s indeed not imaginative, if that’s the best currently-known way to do things, then why shouldn’t they copy it? It doesn’t make sense to do something that is not as good as others, just to be different. 🙂
Gnome on Ubuntu has the same sort of dock, as does Pantheon. Default Gnome is similar. KDE Plasma will soon have a floating panel too.
It looks like the Next designers were really on to something all those years ago. 😄