Melania is setting a precedent that the White House can and should be used for personal gain. Maybe you think the function of politics is to individually get out ahead, but I think public office should be mutually exclusive to private life otherwise accountability of elected and appointed officials is lost.
It’s like when Scalia refused to recuse himself from cases he had monetary interest in. Sure, it doesn’t directly hurt many American people, but it still shows that one of the highest judiciary officials in the land cares more about himself as an individual than upholding the law and respecting citizens.
The Founding Fathers didn’t set up the government as another aspect of capitalism. It’s supposed to ensure rights. That element of the public utility of government is compromised when individuals use their public power for private gain.
I know Melania isn’t a publicly elected official, but she’s essentially a Trump appointee, and it cannot be denied that the First Lady has political clout on her own. She is a part of the West Wing as much as Bannon, Miller, etc…