Perhaps not a true counterpoint, but there are systems like the GA144, an array of 144 Forth processors.

I think you're missing the point, and I don't think OP is "being critical of companies making practical designs."

Also, I think OP was imagining some kind of tree based topology, not connected graph since he said:

> ...but it would take talking through up to 15 intermediaries to communicate between any two arbitrary cores.

Are you aware of anyone who has used that system outside of a hobbyist buying the dev board? I looked into it and the ideas were cool, but no clue how to actually do anything with it.