I can't imagine Kirby and Yoshi games come to mind quickly when people think of Nintendo...
While they've both produced some great games, they don't get people talking like Mario, Pokémon, Zelda, Smash, or Mario Kart...
They also don't have much in the way of general public appeal or core gamer appeal when compared to the series mentioned...
And unlike most of the series I already mentioned, I don't think Kirby or Yoshi are selling enormous numbers...
Kirby sells particularly poorly in Europe...
Have a nice day...