I agree that opening up opportunities for other futures is good, but I don't think Dune was a good example of that even if you like the story -- Dune simply avoided the issue by assuming the future would implausibly turn into the past and that technology would be rejected and medieval feudalism and centralized religious control would return. A better, more plausible, future would show, as is often the case, that the technology we think is so ground-breaking today, just is integrated into daily life and hardly thought about rather than disappearing (which basically never happens).