Large vehicles such as SUVs can exude a type of personality. Sometimes its size can be very intimidating to those who aren't used to driving such large vehicles. This can have a negative effect on the brand and the market they are selling the vehicle to.
Crossovers are aimed at city goers who aren't necessarily into going off road. As a designer, you must cater to this market with your design. To make a large SUV less aggressive, softer lines and less drastic surface themes can be used to visually make the vehicle seem smaller. A lower roofline can make the vehicle sportier and make it blend in better in city environment where most Crossovers are purchased.