Earlier quoted context omitted.
Are you aware of the very large number of desktop environments and window managers available on *nix systems? “Skins” were popular in the windows ecosystem around XP, but it was far from the peak of customization.
It was definitely the peak. I was heavily involved in several communities, and also ran plenty of other desktops environments, but XP had the largest following by far. The sheer number of websites devoted to skinning XP was astounding. Popular websites had thousands and thousands of themes. Winamp 3 was thriving too. It was most definitely peak customization.
But r/unixporn disagrees about peak amount of customization.