It's not the first time Harry Kane has gotten a lot of attention from other teams and had the desire to sign him, but at the same time we've never heard anything coming out of him saying he wants to leave Tottenham or anything like that.
He seems to follow what Tottenham decide, when Tottenham want him to stay he will be happy to stay. When Tottenham intend to sell him then he will accept it.
You are right, a great desire must come from himself, he can rebel if he wants to leave. But he is still in a situation in his comfort zone, and does not want to be released from it.
Harry Kane has no desire to leave the club at this point; he wants to continue getting credibility in England; after all, he's a fantastic striker who has earned an extensive number of goals on the goal-scoring leader board. Harry Kane is Tottenham's most valued player, and he has an acceptable possibility of enchanting the frontline next season. The Englishman has been on the rise for some time, with Bayern Munich interested in buying him, but Spurs are demanding a large fee before they will listen to any prospective approaches. Ange Postecoglou, the new Tottenham Hotspur manager, has been appointed on a four-year contract. He will use his time at the club to ensure victory over their opponents.
Harry Kane's remaining contract with Tottenham has 1 year left and until now Harry Kane has not been willing to sign his new contract, I think with what happened to the Tottenham team that never wanted to develop, Harry Kane had to leave to improve his football career.
Now Harry Kane is still 29 years old and that is the most mature age for a football striker, now he has to determine his career, if he doesn't go to a better team now then his career will never develop again and he is the only top player who doesn't have a trophy for now.