Ethereum doesn't aim to store massive data within the blockchain itself. Instead, we're building an additional component into the network, Swarm, which essentially acts as a DHT/DFS. There are already experimental branches within the main repos, they function, but probably at a POC state.
Furthermore, a 1Gbit DL/200Mbit UL link costs $13.70/month where I live, so I think it it is already very much viable, but maybe the distribution will be skewed towards more internet friendly countries :)
When gigabit class connections are pervasive, the idea of paying people to store data in an open web browser is maybe feasible, but certainly not profitable for any involved party.
Before then? I dont even see the point.