Is this something potentially relevant to zynthian?
In My Humble Opinion it is potentially relevant in the long term future - maybe in Zynthian V9 running on Raspberry Pi 9 or Zynia on RISC-VIII.
The hardware support and >8 core CPU would first have to be added to Raspberry Pi or whatever board we’re running on in the 2040s or later decades. The Parallel Element Processing Ensemble (PEPE) by System Development Corporation (SDC) was a very early (mid-1960s) system that needed-benefited from an SMP-NUMA architecture. We’ve come a long way to actually consider it for a musical instrument!
If you’re interested in learning about NUMA I recommend their FAQ which also provides references with more info:
https://lse.sourceforge.net/numa/faq/
edit: Search Terms: Non-Uniform Memory Access NUMA Symmetric Multi Processing SMP
Lets hope so.