His comment has nothing to do with quality of software or quality of support, but is about dealing with NVidia. Trying to work with NVidia (as a hardware manufacturer) must have been frustrating, but that has nothing to do with quality of the software.
The video is 12 years old. A lot changed in the meantime.
AMD has open source drivers and crashes often. NVidia has (or more precisely had) closed source drivers that nearly always work.
Torvalds wants open drivers, and NVidia doesn't do that. NVidia's drivers are better than their competitors by enough to make it worth buying NVidia even when their hardware is objectively worse, so much as I would prefer open-source in principle, I can understand why they don't want to give away the crown jewels.
The video is 12 years old. A lot changed in the meantime.
AMD has open source drivers and crashes often. NVidia has (or more precisely had) closed source drivers that nearly always work.