Anything Sivers says is gold to me but in this case I think you're adding something that makes it a little more correct. Yep, definitely being merely a project makes it easier and more agile, less risky, than if it's formally a company. I think that there's a certain extra invigorating constraint that happens if you also approach a project from the angle of, "How can this make me a big profit?" or "How could this change the world for the better?" and those can give extra motivation and clarifying structure around what would otherwise merely be a hobby project. I think both approaches are good though, based on my experience.
