That's what the current console SOCs pretty much are - intergrated CPU/gaming GPU on one die backed by unified GDDR for both CPU/GPU, though 8 weak cores as it was the only viable architecture AMD had at the time for a console type device.
From what I understand this is still different from the Sony approach where you'd have a weaker GPU, but would offload shaders etc to the CPU which could do this due to it's powerful dedicated vector processing units. Of course this had the flaw of GPUs eventually develping shader capabilities etc and making it pointless - and harder to program for if you have to target PC/xBox etc as well.
Google has done some research into it though it's not very practical https://augmentedperception.github.io/deepviewvideo/