Exclusives do matter, even more so for Nintendo. One of the biggest problems with the Wii U was that Nintendo's release schedule for those vital exclusive games was abysmal. Especially in the crucial first 12 months.
First 12 months of Wii U exclusives...
November NSMBU (Underwhelming paint by numbers sequelitis.)
December NOTHING
January NOTHING
February NOTHING
March NOTHING
April NOTHING
May NOTHING
June NOTHING
July NOTHING
August Pikmin 3
September NOTHING
October NOTHING
But what about Windwaker HD? Sorry but remakes/remasters are available on an older system and thus not exactly exclusive. They also don't tend to move units unless they have Kart in the name.