Internet.org is currently offered on only one carrier (Reliance) and this is a clear net neutrality violation. Even if it were offered on all carriers, this is a violation. Also, this is hypocritical since FB supports NN in US!
What's worse is that some companies are using this as an example to push for legalisation of zero rating. This is worsened by our regulator's stancce which is pro telecom companies.
Even worse is that a lot of decision makers in our country's administration can be misled into accepting the practice as digital status quo, because a large company like facebook says so.
Sometimes preventing fragmentation of the network is more important. A mobile operator can't, for instance, use licensed spectrum to run a service that doesn't interoperate with others or with emergency services - even if it's free.
If Verizon were to sign up for this, it would fall foul of FCC's rules too (it is clearly paid prioritization when all websites that don't pay are blocked.) It's not for nothing that net neutrality laws in a bunch of countries (Chile, the Netherlands, Brazil and probably a few more) explicitly forbid zero-rating.