Kane has been Bayern Munich's goal machine this season and yes, if Kane is suddenly injured then it seems very likely that it will have a negative impact on Bayern Munich's performance. Although indeed, at least Bayern Munich also has other players who are also still reliable but usually, when the team is dependent on the performance of one player and that player is injured. Then usually, the team will really experience a decline in performance too and I hope, Tuchel realizes this so that Tuchel has another plan to make Bayern Munich able to maintain good results even without Kane at any time in the future.
Well, that's why, it's not uncommon for Tuchel to always make time to give Coupo-Moting and Mathys Tel space to play. I'm really sure that Thucel has taken this into account beforehand. BTW, I remember when Kane joined Bayern. in the interview session, Thucel said that it would be very interesting to have the players he was targeting plus other players, namely Coupo-Moting and one of the young stickers they had, namely Mathys Tel.
In the Bundesliga Mathys Tel has never been the main starter, but the coach always gives him the opportunity to play him. It is proven that in his 10 matches with Bayern he has contributed 3 goals. in the Champions League, played 4 times even though he didn't start. However, he was able to contribute to scoring 2 goals.
Likewise with Coupo-Moting, although not as sharp as last season under Nagelsmann. but still, Tuchel always gives him playing time in almost all the events that Bayern Munich plays. and what I said could be the answer you put forward if Kane is injured. By playing the two players I mentioned in this thread as supersubs, the coach also has other plans to anticipate unwanted situations. one of them, as you said. which means, if Kane is injured, they have enough player options ready to play. although there is still a potential risk of decline if Kane is injured. at least, the coach had his plan in place.
Anyway, what I said is based on my personal assumptions.