Yes, I realize that this opinion is not going to be popular amongst the Leica (and other) fanboys and jewellery collectors and to them I say "get over it". You're either an accomplished photographer or you're not.
The camera you use isn't going to help you if all you're capable of is pedestrian voyeurism and holiday snaps. (yes, I'm looking at the many, many owners of expensive gear who have no chops).
Want to be a better photographer? Challenge yourself. Look at images from the past 100 years by photographers you admire. Study, shoot more, then when you think you can't make any more images, get off your ass and go shoot more still.
Want better images? Go wide, get in close. Stop sniping from the sidelines and being cautious. Life is for living and your photographs tell your story as much as they do the story of the people in them. Lose the long lenses and stop taking pictures of people's backs. Drop the pocket-pervert act and make images that say something, but for goodness sake, stop operating under the delusion that the camera you have will somehow make your images better.