Well the argument is that ARM is cheap and good for consumers because it's cheap. I wanted to make it clear that you can't go to ARM and buy <cheap arm chip>. You have to go to Qualcomm or Apple or Broadcom and buy <not quite so cheap arm chip>. So that kinda impacts the argument.
Whatever Nvidia wants to do with licensing they have to combat market forces already in play. There's a market for somewhat less expensive arm chips, for one, so they'd lose that revenue. Two, if they want to royally fuck arm shops and become the only ARM vendor, well, good luck... you just killed the ISA you bought for 40 billion...