I’m surprised to hear you say that. I would consider it perfectly reasonable to use a line graph without a zero-based y-axis to plot gravity against altitude: the underlying reality is in fact a line (well, a curve I guess)! Gravitational force goes down with altitude in a known way! But the effects of altitude on gravity are very small for altitudes we can easily measure, and extending the graph all the way down to zero will make it impossible to see them.
I’m surprised to hear you say that. I would consider it perfectly reasonable to use a line graph without a zero-based y-axis to plot gravity against altitude: the underlying reality is in fact a line (well, a curve I guess)! Gravitational force goes down with altitude in a known way! But the effects of altitude on gravity are very small for altitudes we can easily measure, and extending the graph all the way down to zero will make it impossible to see them.