The technicalities are many and complex, and Assange's legal team has appealed the extradition order on a wide range of technicalities and thus far failed in all of them. But it's beyond dispute that the prosecution claims to want a lot more than mere questions, and it's Assange who has refused to remain in a position which allows for the usual legal process to run its course.

The wider question is whether it is more accurate to claim that Assange has not yet been formally charged with the offences (or had the charges thrown out) (i) because the Swedish prosecution is refusing requests or (ii) because Assange did not respond to attempts by the prosecution to contact him whilst in Sweden (as verified by his own legal representatives), left Sweden on the day an arrest warrant was issued, and then following arrest and bail in the UK took the unusual option of relocating himself outside the reaches of the British police whilst fighting the extradition order in the courts.

I would suggest it's near impossible to believe the former factor is the primary reason no formal decision on charges has been made, even if one feels the rape allegations are extremely unlikely to be true and Assange has good reason to be afraid.