Yes, but that platform has in-package memory? Which is a higher degree of integration than even "soldered". That's the kind of platform Strix Halo is most comparable to.

(I suppose that you could devise a platform with support for mixing both "fast" in-package and "slow" DIMM-socketed memory, which could become interesting for all sorts of high-end RAM-hungry workloads, not just AI. No idea how that would impact the overall tradeoffs though, might just be infeasible.

...Also if persistent memory (phase-change or MRAM) can solve the well-known endurance issues with flash, maybe that ultimately becomes the preferred substrate for "slow" bulk RAM? Not sure about that either.)