Hypothetically, do spaceships fly?

[MAKG1]

So anything non closed or decaying is always in orbit arond .....well, everything?

Sounds like a cop out explanation. Or a way to make equations work that wouldn't otherwise. Every object inboud from the Oort cloud by that definition is in orbit around everything from Ceres to the sun. Something passing between the sun and Vega is in orbit around both?

Cop-out? For what?

What could you possibly do with a convoluted definition of an orbit that you can't do with the existing one?

Newton postulated universal gravitation over 300 years ago. It still works. Everything in the universe is attracted to everything else. What is the point of your distinction, aside from trying to control what a population of scientists says?

You "could" make arbitrarily complex models that make all the same predictions the existing ones do. But no one would give you the time of day if you did.