Rasterization could be simulated in software with some driver trickery, but apparently it has less fp32 performance than the 5090 so it would be significantly slower
Still, a RISC-V based GPU is very weird, normally I hear RISC-V being slower and less power efficient than even a CPU.
I expect it to be bottlenecked by complex brdfs and shaders in actual path tracing workloads, but I guess we'll see what happens.
In theory it should be able to be more power efficient. In practice, less development has been put into RISC-V CPU designs so they are still less power efficient than Arm (and maybe x86 even)