I think you can only get that $100 rate if you're a new customer. I have AT&T Fiber and DIRECTV and when I browse the plans, it quotes me $140 for the unlimited plan before our 24% FAN discount. I'm not losing sleep over it because the unlimited plan is useless to me since there is no personal hotspot allowed. Having personal hotspot is much more important to me than having "unlimited" consumption ability on a 4.7" screen.
Edit: Nevermind...the extra $40 is because we have two smartphones off contract ($40.00 each for the access fee). $40 each month for each phone...just to be able to get on their network. Ugh.
I'm a long-time AT&T customer who had the grandfathered unlimited data plan. I am also a very long time DirecTV subscriber since the early 90's. A few months ago, I switched from that antiquated unlimited data plan to the new one, which I had no trouble getting despite not being a new customer of either service. The new plan saved me a ton of money on the four phones we had in the family. Instead of paying about $250/month, I am now only paying about $180/month.
The new plan is better since it is simpler. It's unlimited phone, data, and texting, unlike the old plan, which was a voice plan with data and text tacked on. And with more phones, it's cheaper, too. AT&T has promised to grandfather this new plan if it ever goes away, a good selling point.
The price increase on the old plan is obvious. They want to get people off of that plan, plain and simple. Since I save money with the new plan, that became a no-brainer.