rSAP is not a specified feature of the OnePlus One, so it"s not a bug. You can only politely ask them to add the feature
The basic problem is that there is no official way to access the SIM card in Android. I use undocumented interfaces which may change with every new firmware release or the functions may even be switched off completely, which happened with the Nexus 5. I guess the new release has the same changes as the recent Sony Xperia updates. That's why you get qmi-error 0 instead of "access denied". I don't think there is a high probability that they enabled rSAP in the new release.