My smart electric meter has a zigbee symbol on it. It's likely a locked down encrypted proprietary network, but it's there. I spoke to the installer and he didn't know what it was but did say they were on their own network. Mesh makes sense too. You can have one of these pick up a neighborhood, and each house connects to all the rest. Can even be flaky, they just need it to connect once per billing cycle.

I see what you mean, but in this case I see it more as them being too far away to benefit from being linked or coordinated. Not a lot of need for smart traffic flow management—but maybe I’m just underesting the local transportation department.