This file system only works on nvdimms, which are typically in RAM sockets. It won't work on normal block devices.

Er, the comment was, "Most filesystem images aren't intended to be ported directly between machines in general."

The entire complaint itself is the fact that this file system isn't able to do what people expect from most file system images (read: pretty much every one, except this one). Citing the fact that this particular one fails that pattern isn't a justification, it's circular logic.