Apple can be accused of many things, but for the failure of Windows Phone and Amazon Fire Phone? This just sounds like the DOJ is desperate to accuse Apple of something, because in reality Microsoft and Amazon, were responsible for the failure of their devices. This is much the same way RIM/Blackberry was responsible for its own demise, for having not adapted to the new landscape.
Until the iPhone came along Microsoft was barely doing enough to evolve the Windows Mobile platform and then was late to provide anything significant. It wasn't help by the fact that many third-party developers were already focusing their energies on iPhone and Android, both of which has a larger user base.
As to the Amazon Fire Phone, I don't know much about it, but if its anything like their tablets, then I suspect it was a low-effort entry market device, that was likely made irrelevant by Samsung, Huawei and a collection of other Chinese phone brands?