If Facebook really wanted to stop this they could make the eggplant less phallic looking or remove it entirely. Almost no one is going on Facebook to actually talk about eggplant.

They don't want users to have the same plausible deniability when sharing a cartoon wiener that they had when adding a cartoon wiener as an option. And honestly, it is probably for the better that sexual harassment via eggplant is now explicitly called out in the TOS.

I don't expect much enforcement of this.

Edit: Wow, the eggplant lobby found my post. To be clear, I'm not against the eggplant emoji, or its sexual connotations, but I am convinced that it gets used exactly the way its designers expected it to be used.