the M1 utilizes it more efficiently than a “normal” desktop or laptop can since there’s one pool of memory for RAM RAM and VRAM.

That’s not how it works, unfortunately.

A UMA (unified memory architecture) enables zero-copy texture uploads and frame buffer access, but that’s not likely to constitute notable memory savings outside games or GPU-accelerated photo editing. Most of the memory is going to be consumed by applications running on the CPU anyway, and that’s not something that can be improved by sharing memory between the CPU and GPU.

And yet [your 64 gigs of ram] still has less bandwidth than the M1

It’s by necessity that the M1 has higher memory bandwidth. UMA comes with the drawback of the GPU and CPU having to share that memory, and there’s only so much bandwidth to go around. GPU cores are bandwidth hungry, which is mitigated by either using a pile of L2 cache or by giving the system better memory bandwidth.