If I don't pay you, but you still come round when I ask, it's still a startup, but with a freemium price point.
If I don't pay and you don't turn up when I want, but you still are washing someone's dishes, it's a side project.
If you don't come and do my dishes, it's a pivot.
Words might need to mean something, but there's already been a lot of drift here.
That's how you end up with the media referring to 10 year old type companies that have thousands of employees as start-ups. I don't think a definition for it is going to get narrowed now, it will probably always be a broad/loose term.
What the definitions agree on is that a startup is company, a business. Making a business involves a lot more than creating a product and is a much more complex undertaking.
If someone starts something, I call it startup.