Starfield's partnership with AMD did not go over well with PC gamers. About 75% of Steam users have an Nvidia graphics card, and the expectation has been that Bethesda's deal with AMD will hold it back from including Nvidia-specific features in Starfield, particularly support for its DLSS upscaling tech, which can dramatically increase frame rates.
In a roundabout way, AMD has now confirmed that Starfield doesn't support DLSS, but also says its partnership with Bethesda doesn't require the studio to reject Nvidia's tech. Speaking to The Verge, AMD gaming head Frank Azor said that AMD asks partnered developers to "prioritize" AMD's own upscaling tech, called FSR, but doesn't demand exclusivity.
"If and when Bethesda wants to put DLSS into the game, they have our full support,” Azor said.
Other AMD partnered games, such as Star Wars Jedi: Survivor, have also skipped DLSS support, but not all of them. Recently released AMD-partnered game Immortals of Aveum supports DLSS, for instance. As for why Bethesda hasn't included DLSS support in Starfield if it's got AMD's blessing, Azor only said that Bethesda's decision to focus on FSR support is "console leverage."
What Azor's getting at is that optimizing Starfield for AMD hardware aligns PC and console performance tuning efforts, since both the PlayStation 5 and Xbox Series X/S use AMD GPUs. It might also help that PC gamers who use Nvidia cards can still get something out of AMD FSR, but the opposite isn't true. DLSS is exclusive to Nvidia GPUs, but any GPU can take advantage of the software-based FSR.
As a consolation prize, FSR being usable by Nvidia cards hasn't done much consoling, though: Nvidia users are still irritated that the AI technology designed to take advantage of their specific hardware, which is going to give them the best results, is not available in a major game. Cyberpunk 2077, Diablo 4, Forza Horizon 5, Call of Duty: Modern Warfare 2, and a number of other big recent games support DLSS.
It isn't uncommon for new graphics features to be added to games after launch, though, so it's possible we'll see DLSS patched into Starfield. And if it doesn't happen officially, it'll probably happen unofficially: One modder, PureDark, has already stated their intention to mod DLSS support into Starfield, though it bears mentioning that their new builds are released on the other side of a $5/month Patreon paywall.