This isnt impossible to happen. Kane already wanted to leave the club last season due to him being unhappy. But the leagues are o most starting around 10 days until they do and i think most of the teams are complete already. While Bayern Munich still needs a striker so i think anything can happen.
This was before Conte took over Tottenham and things could be way different for him now and it was Conte that actually bring him back on his form after being unable to score for the few early games. While it actually looks not impossible to happen, he might decide not to leave though especially with Tottenham finishing 4th and have a shot on UCL so there isnt any reason for him to move