Just a minor thought connected with the orthogonality thesis: if you claim that any superintelligence will inevitably converge to some true code of morality, then you are also claiming that no measures can be taken by its creators to prevent this convergence. In other words, the superintelligence will be uncontrollable.
There are philosophers who believe that any superintelligence will inevitably converge to some true code of morality, and that superintelligence is controllable? Who?
As far as I can tell, it's pretty common for moral realists. More or less, the argument goes: