Hardware drivers certainly can be annoying, but a hobbyist struggling to bring big GPUs’ hardware drivers to a random platform is not at all indicative of how hard it would be for a company with teams of engineers. If NVidia wanted their GPUs to work on Raspberry Pi, then it would
already be done. It wouldn’t be an issue. But NVidia doesn’t care, because that’s not a real market for their GPUs.
Most OEMs don’t have much hardware secret sauce besides maybe cameras these days. The biggest OEMs probably have more hardware secret sauce, but they also should have correspondingly more software engineers who know how to write hardware drivers.
If Qualcomm moved their processors to RISC-V, then Qualcomm would certainly provide RISC-V drivers for their GPUs, their cellular modems, their image signal processors, etc. There would only be a little work required from Qualcomm’s clients (the phone OEMs) like making sure their fingerprint sensor has a RISC-V driver. And again, if Qualcomm were moving… it would be a sea change. Those fingerprint sensor manufacturers would absolutely ensure that they have a RISC-V driver available to the OEMs.
But, all of this is very hypothetical.