Interestingly, back in the days when Usenet was a big thing, the big nodes that carried the binaries newsgroups didn't use NNTP to exchange messages. There was too much latency in the protocol. They had duplex protocols that attempted to make the most of the link bandwidth in both directions.
Going back to the UUCP distribution model is actually a step back from where NNTP was.
Additionally, if one has a mechanism for reliably and securely distributing files, which is what NNCP is claimed to be, this does prompt the question: Why on Earth would one layer Usenet on top of it in order to do the same job of sending files around? Especially if it were the traditional Usenet model that didn't even include yencoding, let alone MIME and content signatures? Why would one care about binaries newsgroups if one already had a self-styled "darknet" binaries distribution system in place as the underlying transport mechanism?