You are saying that, like Nvidia GRID drivers are open-sourced while in fact they're super far from being that. In order to download drivers not only for hypervisors, but also for guest VMs you need to have an account in their Enterprise Portal. It took me roughly 6 weeks of discussions with hardware vendors and Nvidia support to get a proper account there. And that happened only after applying for their Partner Network (NPN). That still doesn't solve the issue of how to provide drivers to guests, except pre-build a series of images with these drivers pre-installed (we ended up with making a DIB element for that [1]). Not saying about the need to distribute license tokens for guests and the whole mess with compatibility between hypervisor and guest drivers (as guest driver can't be newer then host one, and HVs can't be too new either). It's not that I'm protecting AMD, but just saying that Nvidia is not that straightforward either, and at least on paper AMD vGPUs look easier both for operators and end-users. [1] https://github.com/citynetwork/dib-elements/tree/main/nvgrid
As for AMD cards, AMD stated that some of their MI series card supports SR-IOV for vGPUs. However, those drivers are never open source or provided closed source to public, only large cloud providers are able to get them. So I don't really recommend getting AMD cards for vGPU unless you are able to get support from them.