If you prefer polarized opinions you can find that on any mainstream news venue. In real life people tend to have nuanced and conflicted opinions about many things.
They're trying to make some very serious criticisms without detracting too much from the fact that Internet.org actually got off their arses to do something about the digital divide.
I think its fair. They're trying to give some degree of credit where its due, as opposed to an all out attack. Its hard for me personally to agree with an all out attack piece when I'm conscious of the seemingly good intentions of the project (conspiracies aside).
That is just the technical issue they are against. They also oppose the internet having singular entities acting as gatekeepers. Here is the summary from the last paragraph.
We have confidence that it would be possible to provide a
limited free Internet access service that is secure, *and
that doesn't rely on Facebook and its partners to
maintain a central list of approved sites*. Until then,
Internet.org will not be living up to its promise, or its name.
Although slightly more nuanced than a blanket YES/NO, it would have been more helpful if there were more concrete suggestions on acceptable process mechanisms for 'limited free Internet access'.