The most recent example has had "major criticisms" because it centers a historical figure who happens to be black. (There was almost zero bellyaching about accuracy when the same figure showed up as a boss/side character in more fantastical takes on medieval Japan, including one in which he sics a ghost Atlas Bear on the PC.) There is a kernal of virtue wrt the issue of representation and appropriation, but most of the raging is driven by racism.
I do want to lend support to the idea that he series tries to balance accuracy with its gameplay/narrative foci, though. IIUC, they get a lot of details that Hollywood movies and even documentaries get wrong (by virtue of digital production). Origins and Odyssey included modes that allowed player to move through the world as if it were a living museum, reading passages about people and places as they were encountered.
Overall, it's nice when artists dealing with historical subjects understand that they're presenting imperfect models of the past, and state so, so that viewers can consider what might be accurate and what might not be.