Not solely Kane's responsibility; Bayern Munich has lately experienced some problems. The team has to decide on its tatics and approach as well as maybe bring in a fresh manager. One could find the solution in Vincent Kompany. He is an excellent coach; he may be the one to enable Bayern Munich to once more be glorious
Let's be nice to Kane. He is performing at world class and is doing all he can. It is the team that has to get moving to help him
The fact that Bayern didn't win a title is definitely not Kane's fault. As you wrote, he scored a lot of goals and actually did his job well. Bayern Munich had a lot of injured players last season and constantly had problems because of that. I'm sure that they have a very good chance of winning a title this year, at least in the German Bundesliga, but winning the CL will be difficult.
Whenever Real Madrid reaches the finals, they must win it because luck is more on their side in the league than another league or club. The added advantage is that they have world class players who are capable of making their luck to shine.