But the fact of the matter is that all assumptions made in all sciences are clearly false. Physicists, the most successful of scientists, routinely assume that the table is frictionless when called upon to model the motions of billiard balls. They assume that the billiard balls themselves are solid objects. They assume that objects fall in vacuums.
All scientists make simplifying assumptions about the world, because the world itself is too complicated to study. All such assumptions are equally false,