Investigations into the Starfield preload files reveal a distinct lack of Nvidia DLSS or Intel XeSS footprints, suggesting it will only support AMD FSR.
Sure, if it runs properly without upscalers that's great, but that doesn't mean it should be released without them either.
DLSS/XESS are very easily implemented, they aren't because AMD is preventing it.
FSR2 is kind of the most important upscaler to me though, as it works on the Steam Deck where it's likely desperately needed, and while XeSS technically works on the Steam Deck, the (negative) performance impact of FSR2 is way lower.
It's also always nice to see all upscalers in the same game just so we can compare them in their most up-to-date versions.