It's AT&T's own fault for offering a service that people like to use, unlike most of their service offerings. AT&T should add the necessary network capacity to handle their iPhone customers or get Apple to help carry the load.
And there are no requirements of hand-like appendages required to 'write' for Slate, Creston, speech-to-text makes them unnecessary.
And even if AT&T did this, it wouldn't change shit. Does that Slate numbnut really think that if AT&T raised the price from 30 to 40 bucks, all those iPhone hoggers would stop using the network so much? What a bunch of bullshit.
They use the network because they WANT to use it, and they get an unlimited plan so they can use it as often as they want to. Charging them an extra 10 bucks isn't going to change shit. Maybe if they made the unlimited plan 200 bucks, people would start using it less.
I think the only requirement to write for slate is that you have some form of hand-like appendage.