Frutiger Aero was never called like that. It was just a non-copycat gloss theme cleraly inspired from OSX' Aqua design. Even KDE3 did that for some time (Everaldo/Crystal icons, Keramik...) were rounded, glossy designs were hip and transparencies with XRender were everywere.
Both desktops tried to create someting shiny without being too close to Mac OS X.
TBH KDE has better themes like the Slick icon set and plain but contrasted widget and menu themes, kinda like the semi-flat theme from Office 2003 (was it the .Net theme?) or something like that, which was modern but not baroque and overloaded like Keramik or XP's silver theme with too many gradients.
That style would modernized would be several times than the unusable flat themes from today. Kinda like Zukitre for GTK2/3/4 under GNU/Linux and BSD desktops (ad QT5/6 being set to match the GTK3/4 themes under the settings).
> Frutiger Aero was never called like that.
Indeed, the term "Frutiger Aero" was not really used among geeks in this time; I had to look up Wikipedia to get its precise meaning:
> https://en.wikipedia.org/wiki/Frutiger_Aero
On the other hand, basically everybody who had an opinion about Windows's design used the official terms
- Windows XP: Luna; see https://en.wikipedia.org/wiki/Windows_XP_visual_styles
- Windows Vista, 7: (Windows) Aero: see https://en.wikipedia.org/wiki/Windows_Aero and Liquid Glass (though the latter is an Apple term): https://en.wikipedia.org/wiki/Liquid_Glass
- Windows 8, 8.1: Metro; see https://en.wikipedia.org/wiki/Metro_(design_language)