The biggest question left unanswered in my mind is the role state will play in software of the future.
That seems like an absurd statement, or a naïve one at the very least. State is everywhere:
The values held in memory.
Data locally on disk.
Data in-flight that is being sent over a network.
Data stored in the cloud, including on a database, remote filesystem, etc.
Certainly all of these kinds of state will continue to exist far into the future. Data is king, and is one major factor that will drive the shift to parallel computing. The question then is how will concurrent programs interact with this state, read and mutate it, and what isolation and synchronization mechanisms are necessary to do so?