As it stands we get the following warnings from API:
WARNING: API warning (revisions): The parameter "rvcontentformat" has been deprecated. WARNING: API warning (revisions): Because "rvslots" was not specified, a legacy format has been used for the output. This format is deprecated, and in the future the new format will always be used.
(The QueryGenerator does not add rvslots autoamatically because it is not compatible with rvcontentformat, see T205210)