ND is important for polemic works

That's precisely the reasoning behind the various non-free provisions in the GFDL, which were designed to ensure that the FSF's message was fully and accurately conveyed in its distributed publications.

In practice this hasn't been necessary. It is *possible* that a malicious actor can take a program distributed under the GPL, for instance, insert blatant bugs and misfeatures, and attempt to pass it off as the original author's work. Maybe if we still lived in a world where software and books were distributed exclusively by couriers lugging large brown parcels around that might be more effective, but in practice it doesn't happen. There is little evidence to suggest that the GFDL's non-free provisions have prevented a real problem.

As as the original piece says, if you can't build on a work then it isn't part of the commons anyway. So why is it a CC licence at all? As it isn't part of the commons, the author need not care for interoperability in the slightest, so it's a waste of time to have a standard licence.