It's a shorthand for the 'academic standards' that spotlight (IMHO) a well deserved connotation of virtual soviet style political control. History and Archeology are alive and changing because of evolving contemporary filters that open vistas to some areas of a new find, and close off others.
But maybe I'm rambling on about stuff you already know about. You probably agree with me that the Mission Dolores Mural article, like all such reports, has to be read with an understanding of which academic bias exists. In this case, the article seems to fall into the old 'native Americans were slaves' doctrine. It's wrong (again IMHO) to suggest that the drawings were forced and not, as you (and I) believe, "motivated by the wish to express religious beliefs."