You needed a CB radio, something you could not use for anything else. Most CB's were installed in cars. Base units cost more, as did hand held models. Buying a model for a car and using it in the home? Possible, but not for the average person. Twitter? All you need is a phone or a computer -- something many people already have. The "entry" into Twitter is cheaper/easier, which is why it might be more widespread, but I think the comparison is valid.
Except for the fact that in some very real ways the CB radio was actually useful. Useful primarily for finding out where the police were on the interstate, so you wouldn't get a ticket for going over the new, and much hated 55 mph speed limit, useful for calling for help traveling or talking to your buddies following you in the next car. Weather and road conditions passed from truckers and motorists etc. They certainly created and highlighted a subculture many of us would like to think of as unintelligent and coarse, that is truckers, truck stop folks and the very rural, but CB communications was also very practical. No one has tweeted to me that there was a speed trap around the bend.
Get off my lawn.
I'm willing to bet that paying for these employees cell phones was seen as more valuable to the employees than it actually cost the state, therefore it was cheaper than paying however much more cash they would see as the same benefit, over time, and large enough numbers the quality of the workforce in question will decrease by the fifty-some dollars a month per person the state is saving. So basically the whole story is a big fat "yawn" hidden pay cut. Not your rights online, not a sea change, just dumb grandstanding by an aging dork.
The sum of the Universe is zero.