The article touches on this a bit, but one of the quirky things about the original Voodoo and Voodoo 2 were that they lacked 2D entirely. You had to use a short VGA passthrough cable to some other 2D card. This also meant that they only supported fullscreen 3D, since 2D output was completely bypassed while the 3dfx card was in use.
The Voodoo 3 finally came with 2D, but I think I jumped ship to Nvidia by then.
And the lossy, double-clutched analog nature of this crushed 2D clarity IME. I could immediately tell the difference just looking at a desktop screen. It was by far my biggest grievance and resulted in me staying away until fully-integrated solutions were available.
The Voodoo Rush a year before that also had problems - it was a Voodoo 1 chip, but coupled to a slow 2d processor (back when that still mattered, like for just drawing windows or wallpaper in Windows) and had some compatibility problems.
It took until 3dfx's third iteration, with the Voodoo 3, to finally get 2d/3d integration right.