people from AgID (Agenzia per l¹Italia Digitale) report a comment related to this issue:
For the AgID people, the usage note of the property "Authority" (dct:creator) of the Dataset Class seems not to be sematically conformant with the definition of the property dct:creator given in DCMI Metadata Terms ("An entity primarily responsible for making the resource"). Rather, it seems more conformant with the definition of the property "dct:rightsHolder".
The GeoDCAT-AP working group started discussing about this, in relation to the use of responsible party roles in INSPIRE.
According to his email, Andrea Perego proposes to solve the issue by providing best practices (following Geraldine's suggestion). As far as the agent roles supported in DCAT-AP are concerned, the possible replacement of dct:creator with dct:rightsHolder might affect the mappings defined in GeoDCAT-AP for responsible party roles.