I wasn't a big GNOME fan even back then, but I agree, the Bluecurve theme was lovely, and it looked great on both GNOME and KDE. KDE has never looked so good, before or since.

It honestly escapes me, given the vast variety of themes out there, that since the RHL era, no other distro has ever coordinated its themes across all desktops that way. It's a great way to bring a coordinated look across a distro.

Ubuntu's old Ambiance and Radiance themes have been a strong part of its brand for a decade or more. Why doesn't Kubuntu, Xubuntu, Lubuntu etc. modify and adopt the standard Ubuntu house style?

Fedora's GNOME themes are also great looking, even speaking as someone who doesn't like the desktop itself. Jakub Steiner is a design genius: https://jimmac.eu/

The other Fedora respins should adopt the look, and present a unified brand.

Same for openSUSE, Debian and any other distro with multiple desktops.