depend how much is YOUR expectation here.....
remember.. mario is usually a leg game.... and it does not need to sell 10 millions to break-even....
and nintendo get most of the profit, so the return of money in each game sold is much more than for example rockstar's game.
so no it wont be a flop in terms of profit, but mario games have too much expectations.... it will have money but it wont be the best selling games of all time.