There is an error though in your thought process.
- You will still have your phone
- Datacenters are more easily able to be environmentally friendly through improvements in efficiency (including through renewable energy consumption)
Additionally Datacenters are built for maximum workload which means there is lots of wasted potential much of the time easily allowing to pull the workloads of feed documents to devices.
Long term the hope is that more Datacenters start moving to more eco-friendly locations and leveraging more environmentally friendly processes as well. I think there are starting to be some located in locations that can be run through solar. Even if solar is not as efficient today its all about building a blueprint for future improvement IMO.