Great teams like Real Madrid, Bayern, Barcelona, etc stack their squads with the best players available. Suarez alone was probably the best striker in the entire English league, yet now he plays second fiddle on Barceona. Teams are more equal in the upper echelon of European competition, but in the mid to bottom tier, the English teams are better (and buy better players too).
That aside, Harry Kane is a good striker. He just hasn't adapted to teams watching his tape yet. I didn't even know soccer teams watched tape but apparently they do. He needs to be more creative with his finishing.