Your last sentence gets at the heart of my point. If you wanted me to come on board with your idea that builds on hyperloop, I wouldn't be "agreeing that that'

Your last sentence gets at the heart of my point. If you wanted me to come on board with your idea that builds on hyperloop, I wouldn't be "agreeing that that's a pretty cool idea and should be on your list." I'd be agreeing to actually build it somehow. So the standard for cofounding something is a million times higher than the standard for putting it into some list of ideas.