Comment by angoragoats

This might be nitpicking but 1) the ram is not integrated into the chip, per se, it's still discrete and soldered on a PCB right next to the CPU, and 2) the increased speed comes from additional memory channels built into the M-series CPUs, not necessarily the fact that the memory is closer to the CPU.

It is true that it's not currently feasible to have socketed memory in a laptop offering 8+ memory channels to enable 200GB/sec+ bandwidth, but you can absolutely get the same (or greater!) memory speeds as an M-series CPU from an x86 desktop workstation.

If Intel/AMD wanted to prioritize memory bandwidth, they could probably work with JEDEC or another industry org to develop a new standard for socketed memory with multiple channels per socket, to enable the kind of speeds that Apple offers. The fact that they haven't (to my knowledge) indicates to me that they don't see it as a big enough priority or benefit.