To bolster your point: Honestly they don't need to do much - the infrastructure is already there as a matter of being able to turn people's service up/down/on/off.
There is always a provider-managed CPE device that functions as the service demarcation point. This is the point where your contracted service speed is enforced (shape + egress queue and ingress policing).
You can have literally whatever router (dumb, smart, next-gen, whatever) spewing bits at X rate. The CPE will essentially normalize (police) that bit rate to your contracted speed (upstream scenario).
There is always a provider-managed CPE device that functions as the service demarcation point. This is the point where your contracted service speed is enforced (shape + egress queue and ingress policing).
You can have literally whatever router (dumb, smart, next-gen, whatever) spewing bits at X rate. The CPE will essentially normalize (police) that bit rate to your contracted speed (upstream scenario).