I personally have collected enough reason to be very skeptical against such criticism. The first Swedish prosecutor dropped the case. When it was restarted by a second prosecutor, several uninvolved lawyers looked into the case on behalf on news agencies and conclude that the case had zero chance of going anywhere. When compared to rape cases in Sweden that get dropped, get not-guilty in court, and the small number that get a guilty verdict, you either need to have physical evidence of violence/drugs where a medical expert use their experience to claim rape, a video recording, witnesses that strongly (and seems more common than not to fail here) to show that the victim was incapacitated when going to sleep, or a confession. In contrast to most cases all the details for Assange case has been leaked and it has shown none of those critical components for a successful case. In addition we get some more warning clocks ringing when the European arrest warrant made a record for the lowest number of potential year in prison. A second record was achieved by the the amount of money spent in regard to the number of potential year in prison.
It could be a unicorn, a one of the kind where all the stars align to a guilty verdict, but the case smells political. The rational behavior when the legal system turn political is to run and hide.