Keeping tight control is a *good* think in user interface design strategy; it provides a more focused structure and simpler environment, which were their goals.
The mistake the Gnome developers made was calling the new desktop "Gnome 3". Had they presented it as an experimental new environment and named it "Project Harmony" or "Desktop Zen", or something like that, they would have stepped on less toes and met less resistance to the radical changes, and people would have seen it in better light.
Of course they would have had less audience, as distros wouldn't have adopted it so quickly. That trade-off was their choice, but I think "Linux is awesome! There are three good major desktops now!" was a better selling point than "They've updated Gnome, and it sucks".