This sounds like essentially a blog article, where the writer renders his opinion that their practice of digitizing and loaning digitized books is legally problematic. This is a subset of all the content they are processing, and it sounds like there's not even widespread consensus this practice is problematic. Anyway, he makes the point in the article itself that there hasn't been a ruckus raised about it yet even by the people you'd expect to, the Author's Guild that reacted so much to the original Google books digitizing project.

This doesn't convince me that archive.org is a piracy site. Only that there is some disagreement by the blogger (and perhaps, his affiliated organization??) about the legality of this novel approach of digitizing and loaning modern ebooks, which are a small subset of their collection. He freely admits that most of their content is not problematic, if I understand him correctly.