Last week Kendall Jenner tweeted the Hollywood Reporter front cover that she and her family feature on. She captioned the pic with "sister power... girl power 👊🏽".
sister power...girl power 👊🏽
In case it isn't clear, this is how the emoji would look on an iPhone.

Twitter / Screenshot
That would be emoji number 4.

apple / screenshot
The one that is in the middle of the emoji skin tones.

apple / screenshot
People noticed that Jenner used the emoji and called her out for it.

And are asking why.

@KendallJenner Me looking at the color of that emoji