But are all sides of the car in the optimal angle towards the sun?
No, but neither are solar panels on houses. For the car, it’s ideal to park facing North/South. For stationary solar panels, it’s ideal to have solar panels mounted on a pan/tilt platform so they can always face the sun, which is rare.
No trees or buildings near your parking spot that could shade your car?
It’s pretty clear at my house, I have a designated outdoor parking space. Not perfect but definitely sufficient for my commute. At my work there aren’t any obstructions.
If these panels didn’t go into a car, someone else would mount them to a roof instead.
No, they developed and patented their own tech for curved solar panels.