An auto-industry-borrowed technique for Future Backward (Big-S Strategy): build a prototype of each of the roughly three generated candidate futures, purely to inspire rather than to ship. Like a car-show concept car, none of the three is meant to go into production as designed — the point is to make an abstract future tangible enough for a team to react to.
The output of each prototype isn't the prototype itself but a single compelling nugget extracted from it. That nugget is what carries forward into further UXR testing and, eventually, a live product test — the prototype is discarded once it has done its job of provoking a reaction.
One of the few concrete artifacts in an otherwise abstract long-horizon exercise: without something to point at and react to, a 5–10 year vision stays too vague for a team to argue about productively.