Hello wojtek,
The inconsistency is related to later introduction of Metashape.Tasks class than common methods. Tasks class is more close to the internal representation of the processing features and therefore is also similar to NetworkTasks implementation, having similar naming convention for the parameters/arguments used.
We'll see, if we could bring everything to the same convention, but as it appears to be a major change, I think it could be expected in the version 1.6, otherwise the scripts compatibility within versions 1.5.x could be broken.