If you're open to technical feedback your last comment, I've worked on these kinds of systems, have architected and built things even far "weirder" and these products have shipped and out in the real world, in silicon, in FPGAs and things between.

The reason an FPGA is a more suitable platform is you can translate "physical effort of making PCBs" into "creating a design in an infinitely re-programmable platform" and change your design as needed to your hearts content.

In fact, the original design of RISC-V included a bus called 'TileLink' to enable 'Many core' arrays of RISC-V processors.

Translation: You can pare-down open-source RISC-V cores and use TileLink and emulate CM or build something more complex as you see fit since that was built into the original open-source RISC-V specs.

FPGAs are their own joy and pain for sure and it's not as "cool" to re-program a blackbox on a PCB as it might be to make your own thing, so all depends on your goals.