I think it's a fair point that these companies aren't building a sharing economy. They're building companies that let people sell individual surplus of capital or time or skills through a convenient platform. That might not be sharing, but there's real economic value in that. They wouldn't be able to take a cut from these small transactions unless they genuinely offered some valuable service to the other parties. I just recently stayed in a wonderful AirBNB apartment while on a trip, and I know I wouldn't have managed that without the AirBNB service, and I know I would have paid more and gotten less for a hotel.
The author assumes--wrongly, from my experience in public policy--that the status quo organizations and regulations exist for the common good. Some do, but many don't. Lots of bad laws and crooked organizations raise unjustifiable barriers to entry--not just for Silicon Valley start-ups, but for the mom-and-pop businesses too.
I can't say for sure whether Peers is good, bad, or neutral. I can say with certainty that this article is heavily biased, ignorant of how most nonprofits work, and ignorant of the public policy process.