It's a valid concern, but it's a contractual problem more than a technology one.
Companies doing smart meters are not taking the basic subscriptions made for the public. They have dedicated contracts with their telcos, with commitment for long term support. So these smart meters companies have visibility and guarantees, and are updated on the telcos long term plans. That's what enable them to deploy meters with 15 years of life span.
The way it works in practice is that telcos may close their "old" 2G (or 3G, but 3G is not used much there. Most jump direct from 2G to 4G) networks to the public, but keep some capacity in operation for those industrial users only for a lot more time --- as long as needed per their contractual obligations. The general public won't see this, as these frequencies will be denied to anyone but specific industrial subscribers. There's no need for much capacity either, as smart meter don't "talk" much.
Another way these long term needs can be addressed is through standard support. For IoT, LTE (perceived as a 4G technology) meets the 5G requirements from R15 onward. And there's work to support these LTE IoT devices (LTE-M, NB-IoT) over "5G" (the tech is called "NR", or "New Radio". Engineering naming ;) channels onward, so there won't be a need for dedicated LTE IoT channels for IoT, as is done for 2G.
So independent of the way it's done, the cellular industry does support long term commitment for M2M/IoT. But as you can see, it's geared toward big customers in practice. In theory one could think about ways to open this to smaller clients (cloud like subscription and access), but I'm not sure anyone does this. It's not a tech problem, more a cultural and business one.
Companies doing smart meters are not taking the basic subscriptions made for the public. They have dedicated contracts with their telcos, with commitment for long term support. So these smart meters companies have visibility and guarantees, and are updated on the telcos long term plans. That's what enable them to deploy meters with 15 years of life span.
The way it works in practice is that telcos may close their "old" 2G (or 3G, but 3G is not used much there. Most jump direct from 2G to 4G) networks to the public, but keep some capacity in operation for those industrial users only for a lot more time --- as long as needed per their contractual obligations. The general public won't see this, as these frequencies will be denied to anyone but specific industrial subscribers. There's no need for much capacity either, as smart meter don't "talk" much.
Another way these long term needs can be addressed is through standard support. For IoT, LTE (perceived as a 4G technology) meets the 5G requirements from R15 onward. And there's work to support these LTE IoT devices (LTE-M, NB-IoT) over "5G" (the tech is called "NR", or "New Radio". Engineering naming ;) channels onward, so there won't be a need for dedicated LTE IoT channels for IoT, as is done for 2G.
So independent of the way it's done, the cellular industry does support long term commitment for M2M/IoT. But as you can see, it's geared toward big customers in practice. In theory one could think about ways to open this to smaller clients (cloud like subscription and access), but I'm not sure anyone does this. It's not a tech problem, more a cultural and business one.