But that unfortunately erodes the free-as-in-beer advantage, since in this situation the software is effectively proprietary, and competes with proprietary code on an equal footing: bang for the buck.

"If we're going to pay to license freeware code as proprietary, let's look at all proprietary alternatives."

Is there any evidence that the author will sell commercial licences? Other comments are describing him as a strong proponent of free software, so it seems very unlikely that he is interested in selling proprietary licences.