(Probably fake) racist Mario 64 prototype found

I found a post over at Assembergames by user Joe19 talking about a Super Mario 64 prototype that had a little bit of a strange message in it. Let’s have a look:

Now this definitely is a bit odd… I had a look through the thread and it seems as though the cart is genuine. Someone would have to go through a whole lot of effort to hack this comment into a ROM, burn it onto a rare development cartridge and then sell it. So I think there are two options:

1. Some kind of trickery/photoshop is used to make that text appear on the screen. For all we know, the TV could be displaying an input from the back rather than the front imput from the Nintendo 64.
2. This is really a Mario 64 prototype, likely from the stage where they were translating it from Japanese to English and someone put this in as a joke. This would mean that we’re dealing with an ultra rare prototype cartridge.