It doesn't say which generation of core is it. Are they the same as the one in Elite Gen 5?

Has Microsoft actually pushed for the ARM changes? Because I don't believe Qualcomm can do it alone.

Yes, it's the same Oryon V3.

AFAIK Windows on ARM is completely pushed by Microsoft (obviously they're limited by their own competence) and Qualcomm has been kind of phoning it in.

FOSS support for Windows ARM has been hampered by Github (owned by MS) not supporting free Windows ARM runners. They may be finally getting their act together but are years late to the game.