Negative reviews with 'shoulda done this'

I think the reviews where they complain about "realism", or say it was a good premise but it could have been done better, are lame. If this were such an easy thing to do, why is it that this is one of the only movies in the last 50 years to execute the premise?

The only things like it I can recall are "Black Like Me," a sketch by Eddie Murphy on SNL, and "White Chicks."

All those movies are about whiteface or blackface, not speculative fiction.

(I haven't seen the film in 15 years so please bear with me.)

I think the film is mostly about racist narratives in media, politics and day-to-day racist talk, and the representations of Blackness and Whiteness, not about reality. It's a hyperreality, in high contrast. Films and media rely on stereotypes and simplifications to be able to tell the story.

The effect of switching races is to creating a jarring experience for the viewer. Clearly it worked, because there were 45 reviews.