is dune sci-fi? or more dystopian
Yes, from the prequels to the original novels.
In the prequels, humanity is enslaved by an oppressive AI. The Butlerian Jihad is triggered by the revelation that it is terminating healthy pregnancies to maintain the population at the level it desires. And there are human slaves experimented on by the machines. See the first Mentat.
In the original Dune novels, humanity lives under the oppressive rule of an Emperor and noble houses. Everyone and everything is bound by the Spice on Arrakis. Control of this substance essential to long life, access to genetic memory and the ability to travel in space depends on it. This prevents humanity from expanding and control of the critical resource props up the current social system. Paul’s coming of age and ascension to power doesn't change this.
