The grills of articulated trucks/16 wheelers aren't aerodynamic and are testament enough on their own tbh.

The stats back it up - one long-term tracking project in Denmark found an 80% decline in insect abundance between 1997 and 2017. The 'Bugs Matter' initiative in the UK similarly found that the number of flying insects hitting car license plates dropped by up to 72% in under two decades.

https://www.theguardian.com/environment/2020/feb/12/car-spla...