Cuda was first, and worked well out of the gate. Resources that could have been spent improving cuda for an ecosystem that was outright bad for a long time didn't make sense.
Gsync was first, and was better because it solved a hardware problem with hardware. It was a decade before displays came default with hardware where solving it with software was short of laughable. There was nothing nvidia could have done to make freesync better than dogshit. The approach was terrible.
DLSS was first, and was better because it came with hardware capable of actually solving the problem. FSR doesn't and is inherently never going to be near as useful because of it. The cycles saved are offset significantly by the fact that it needs its own cycles of the same hardware to work.
Opening the standard sounds good, but it doesn't actually do much unless you also compromise the product massively for compatibility. If you let AMD call FSR DLSS because they badly implement the methods, consumers don't get anything better. AMD's "DLSS" still doesn't work, people now think DLSS is bad, and you get accused of gimping performance on AMD because their cards can't do the math, all while also making design compromises to facilitate interoperability. And that's if they even bother doing the work. There have been nvidia technologies that have been able to run on competitor's cards and that's exactly what happened.