At least in theory it should be possible to run Fedora/RISC-V on this (https://fedoraproject.org/wiki/Architectures/RISC-V) although at only 2GB the memory size is underwhelming. I have backed it.

Can anyone speculate if it would be possible to add NVME using something like this? https://www.amazon.co.uk/StarTech-com-M-2-Adapter-Profile-Ex...

Why this half backed open SoC? The CPU has an open source instruction set while the FPGA is complete proprietary garbage.

All FPGAs are "proprietary garbage". Some have been reverse-engineered (like the Lattice) with great effort, but that's the only difference.

Well by that strict definition all of them are indeed proprietary. But in effect some Lattice and Xilinx FPGAs are usable as if they were not proprietary.