I don't think it is negativity. Someone else already called it out, but if you were to face east and then travel in a straight line, you would leave Earth's orbit. Thus, the question inherently is taking Earth into consideration. Their definition of "most obvious" is strange because you would encode a globe using spherical coordinates. A "straight line" East in spherical coordinates could be argued to be keeping the polar angle constant and increasing the azimuthal angle which would land you in France. The crux of the disagreement is what "most obvious" means.