I don't know the exact reason why it would be limited to XP, but that's what the minimum requirements state, and I don't think there's any way of getting around that. If you want to find out more info or how to get around it (if possible), I'd contact EA directly and ask them.
It's an excellent game, so I'd hang onto it until you can get Windows XP.
It's an excellent game, so I'd hang onto it until you can get Windows XP.