Nvidia isn’t likely to invest $40B and then do anything to damage ARMs licensing efforts. They are likely to look to find synergies so ARM can incorporate Nvidia technologies and Nvidia can better utilize ARM technologies.
This is a business that has no overlap over what NVIDIA does and maybe NVIDIA could spin off this part of ARM as a separate company, because I can hardly imagine the NVIDIA management focusing in this business, where they do not have any experience.
On the other hand, ARM Cortex-A CPUs are better than those designed by NVIDIA and they are used in products (e.g. by Qualcomm) that directly compete with NVIDIA products.
I cannot imagine that NVIDIA will continue to design better Cortex-A cores and then give them immediately to their competitors.
what would this mean? are there any CPU ISAs with a GPU integrated into the ISA instead of just a peripheral?
That would be amazing. Nvidia has arguably the best GPU designs in the market, this would be a boost for ARM IP business.