Harry Kane is objectively a way, way superior all-around player than both Haaland and Sergio Aguero. I've no problem to admit it myself as a Haaland fan. Kane is a world class goalscorer AND playmaker. However, Kane (and Aguero for that matter) has never been rated as the best striker in the world at the end of [insert season].
A productive goalscorer is generally often the most valuable player (with notable exception). In this case, Haaland makes goalscoring look ridiculously easy in a way neither Harry Kane or Aguero has done.
Neither Aguero or Kane is in conversation among all-time great strikers in football history like Haaland.