Michael Schulson, in an well-reported overview of the commercial capture of OA on Undark:
Instead of an open-access commons run by scholars in the public interest, the new open-access revolution increasingly looks like it will depend on the same big commercial publishers, who, rather than charging subscription prices to readers, are now flipping the model and charging researchers a fee to publish their work. The result is a kind of commercial open-access — a model very different than what many open-access activists envisioned.
The piece quotes Jon Tennant on the oligopolists:
“But at the end of the day, they produce a PDF on a webpageand they archive it,” he said. “That’s basically it. And it costs the same as a car to do that!”