I don’t know if the mockup is what will actually appear in production, but there is some psychology about showing a flower and a smiling black woman. The image plays first to trust (nature, a mother figure, the smile) and if that isn’t enough, secondly to guilt (I need to start trusting black women) to prime the user into accepting the prompt. Imagine if it were a cartoonish Mark Zuckerberg with his tight little smirk, and instead of a flower, a piggy bank.

Facebook isn’t stupid or random. This image must have been very carefully developed and run past some of their staff PhDs. Assuming this is real.