Bootstrapped and infinite runway doesn’t go hand in hand lol.
Runway always costs. By that definition it’s artificially subsidized.
That definition sounds more like a project than a product/startup.
Bootstrap is a business, cash flow is like blood flowing with oxygen in it, so the body can move and go do thing
Steve Blanks’s definition is a good or that a startup is a temporary organization dedicated to finding a repeatable and scalable business model.
Life costs money, if a project is coddled to never become a product. it’s artificially subsidized by an investor (you) and default dead.. and it’s not a business that makes profit to pay the Bills or pay for growth.
Funded startups can have different metrics for growth.