Maybe

We'll just have to wait and see. I think this mod is a little old and since they are taking down all nintendon't related content, it might take them a while to get to this one.

No, actually. They cant remove this. It doesnt have ANY mario content. You have to supply it yourself. This mod has nothing nintendo related in it. But you do supply that content YOURSELF.

yeah, it wont get removed, because you have to supply the rom file yourself, so technicly nintendo has no rights to take it down

Its not possible. Since you require a ROM file (THAT you dumped with your own cartridge!) and Mario is not really a name that Nintendo doesn't own. Also i dont think some game code is fully protected with copyright laws.