Rather confused by this claim that GNOME 2 was helloworldware. GNOME 2 was one of the very few Linux desktops that saw widespread usage within large companies. Red Hat and Canonical had professional offerings based around it. It attracted a small chunk of home users who were pissed off by Windows Vista. So it definitely got UX tested quite a lot. Red Hat Linux actually still includes a builtin clone of the GNOME 2 design just to cater to people who have been using the same UI in a professional setting for decades. They only recently switched away from this classic clone layout being the default.
KDE is the one that was way more community-focused, but it did see a bit of use for professional workstations.
You may be thinking of GNOME 1 - it was incomplete garbage.
No, not really. Early gnome was a joke compared to KDE, in that while KDE could be actually used as desktop, gnome was helloworldware.