The direct increase of revenue comes from more customers arriving now that you're combining a robust network with unlimited data. Both of those things even in isolation are pretty significant attractions; having both of them is even better.
Barring that, however (as I mentioned elsewhere in this topic), congestion issues are already resolved in the wired broadband realm by selling speed rather than data quantity. There's little reason why the wireless world can't do the same by selling access to 2G/3G/4G separately, then making every plan unlimited (or, at the very least, have way bigger caps for everyone, as is the case currently with some of the not-so-great broadband ISPs).
Basically, you'd have T-Mobile's approach, but with a lot more flexibility. In combination with a no-contract carrier (like T-Mobile) or reseller (like Google Fi), a customer could, say, subscribe to a 2G or 3G plan for normal usage, but then subscribe to the 4G plan for a day or so if he/she wants to binge-watch Game of Thrones or somesuch. This way, the congestion issues are addressed (there's a direct monetary incentive for carriers to build more robust networks, since the faster data subscriptions would cost more and generate more revenue) while not imposing arbitrary caps on the quantity of data "used" by a customer. Win-win.
This could be even further extended by providing the 2G and 3G plans with an optional scheme of "we'll give you $X days of 4G per month" (similar to T-Mobile's "we'll give you $X gigabytes of 4G per month"). That way, our Game of Thrones bingewatcher doesn't have to deal with changing the subscription; he'd instead have a week's worth of 4G per month that he could activate on a per-day basis (for example). An even sweeter deal would be for these unused days of 4G to roll over to the next month up to a year (or some other suitably-reasonable length of time), like what T-Mobile already does for its non-unlimited plans.
Barring that, however (as I mentioned elsewhere in this topic), congestion issues are already resolved in the wired broadband realm by selling speed rather than data quantity. There's little reason why the wireless world can't do the same by selling access to 2G/3G/4G separately, then making every plan unlimited (or, at the very least, have way bigger caps for everyone, as is the case currently with some of the not-so-great broadband ISPs).
Basically, you'd have T-Mobile's approach, but with a lot more flexibility. In combination with a no-contract carrier (like T-Mobile) or reseller (like Google Fi), a customer could, say, subscribe to a 2G or 3G plan for normal usage, but then subscribe to the 4G plan for a day or so if he/she wants to binge-watch Game of Thrones or somesuch. This way, the congestion issues are addressed (there's a direct monetary incentive for carriers to build more robust networks, since the faster data subscriptions would cost more and generate more revenue) while not imposing arbitrary caps on the quantity of data "used" by a customer. Win-win.
This could be even further extended by providing the 2G and 3G plans with an optional scheme of "we'll give you $X days of 4G per month" (similar to T-Mobile's "we'll give you $X gigabytes of 4G per month"). That way, our Game of Thrones bingewatcher doesn't have to deal with changing the subscription; he'd instead have a week's worth of 4G per month that he could activate on a per-day basis (for example). An even sweeter deal would be for these unused days of 4G to roll over to the next month up to a year (or some other suitably-reasonable length of time), like what T-Mobile already does for its non-unlimited plans.
There's more than one way to do it :)