In the animation you can almost see a MAJOR flaw in liniear gradients. I filed a bug to the team. No one noticed this for two years?
(Major bug in linear gradient)
On a rectangular shape there is a major angle mismatch between the gradient and the user input via the liniear gradient tool. On highly rectangular shapes liniear gradients are almost unusable.
Here you see the problem in Gravit Designer 1.8. Adjusting the angle to get the desired gradient is like balancing on a line, blindfolded and drunk.