Thanks for sharing this experience. I still wonder about this statement: Why do you think it is that a large company can not simulate a startup environment? I know you mentioned that it can not take the same risks but then again why not creating an independent legal entity with its own brand maybe even through a middleman to increase the distance to the parent?
I have been in a corporate startup myself. I worked several years for Car2go (Daimler daughter company for ride sharing) and there even in a small project that was meant as a startup as well. We probably made many mistakes but one was that it was difficult to pivot because that would require a change to what upper management had agreed to. In a startup if you don't earn any money, you just do something else. But there if we had a structurally independent legal entity without the need to ask for permission to pivot this probably could have been avoided.