"because it's unified" is definitely not the reason.

Here’s a unified AMD with an NPU, and socketed ram:

Note that it’s two generations old, and the newer ones have soldered ram.

	▲	ben-schaaf 4 days ago \| parent [-]
		Every AMD and Intel APU has had unified memory for many generations, as have mobile devices. It's sad how many people Apple's marketing has misled about something that's been standard in the industry for ages.