Nothing is really unlimited anymore. Or at least that’s what carriers want their subscribers to accept, using various tricks and “incentives” to get people to retire their old, grandfathered plans. AT&T has already previously increased the monthly fee on those old truly-unlimited data plans and now they’re adding $5 more to the monthly service fee, in the hopes that those still on it will eventually give up and switch to their newer plans, all of which don’t actually have unlimited data.
Originally, the unlimited data plan, which really has no limits, was priced at $30 per month. When carriers started realizing that their users were doing all sorts of heavy data usage on their plans, therefore slowing down the network, they started coming up with data plans that would cap users once they reached a certain volume. They then tried to lure subscribers to go to these new plans by offering all kinds of incentives. But there are of course holdouts who want to keep their truly unlimited data plans, since they are most likely really heavy users. And so AT&T added $5 to the MSF.
Apparently, $35 is still manageable for these data hoggers and so now AT&T wants to add $5 to the equation. There are no numbers available as to how many switched to new plans during the first increase a year ago, but probably it was low, since they’re now increasing it again. When they did in 2015, they also tried to throttle the original unlimited plans, but that didn’t go well with the FCC of course, and the carrier was fined $100 for this offense.
If you download a lot and video stream so many shows and/or movies, then $40 a month for something that is really unlimited would still be worth it. You probably would rather pay up than transfer to a plan where you’ll be throttled.