So little about chip success is down to just the core. Sure, some basic performance aspects, clock range, area and thus cores/chip. What about inter-core performance? Memory interface?

There's still no real synergy between CPUs and GPUs, even though they get less different with time. No one seems to have a decent plan for how to balance local memory resources with cache-coherency over CXL. Inter-system networking seems to be frozen in 1980 (just with faster serdes). Does in-chip and inter-chip optical change anything, or does it just mean littering the place with tranceivers?