>> Aren't good Graphics IP cores availble to licence from imagination or ARM ?
Yes they are. But general availability at a price is not the same thing as free. I suppose ARM had made their CPUs nearly a commodity, but it's still not the same as open source designs available for free. Graphics and RF seem to be the last holdouts with more vendors offering graphics IP as far as I can tell - or at least having IP even if they don't license it. For RF you don't have much choice.
Most of the value of RISC-V will not really be in free designs though. The GPU is already a commodity because of higher-level standardization in APIs (Vulkan, OpenGL [ES]). It's just hard to design and build good GPUs, which means fewer players in the high end space. Vivante seems like the only really independent GPU design vendor, not sure if you can license Mali for a non-ARM design, you'd at least need to support their peripheral buses.
Yes they are. But general availability at a price is not the same thing as free. I suppose ARM had made their CPUs nearly a commodity, but it's still not the same as open source designs available for free. Graphics and RF seem to be the last holdouts with more vendors offering graphics IP as far as I can tell - or at least having IP even if they don't license it. For RF you don't have much choice.