Hardware

compensating for that with a much bigger L2

If I understand this article and what kopite7kimi said correctly, it sounds like a 33% cache increase, which he assumed meant a 33% memory controller increase. So 128MB, which they derived 512 bit from originally. That's not that huge of a jump of cache compared to the current 96 it seems to me.

GDDR7 is supposed to start at 32Gbps, but there is also some claims of 36 Gbps. If you average to the cache (33%) and memory speed (60%) increase we're talking maybe 45% more effective bandwidth.