That depends on what you mean. Their main market is AI, but their reputation is still built largely on gaming. The two sides of their business are linked like the two sides of a coin and can’t be separated. It’s why they are so fiercely protective of their gaming reputation that they threaten and bribe journalists for favorable treatment and use software-specific driver tricks to artificially bump their benchmark numbers.
From the outside, I don’t consider them “key” for anything. There are other businesses and technologies that could easily replace them.