Based off of this info, I guess the hypermilers should just play classical.

From the study:
On average, drivers lost 25 per cent in range expenditure versus real-world miles
Total test route distance 18 miles
Average range expenditure 22.48 miles
Classical music (111 BPM, Beethoven, ‘Symphony No. 9’) duration: 32.5 per cent of playlist
Range expenditure of the 22.48 miles attributable to classical music: 7.7 per cent
Up-tempo pop (171 BPM, The Weeknd, ‘Blinding Lights’) duration: 10.4 per cent of playlist
Range expenditure of the 22.48 miles attributable to up-temp pop music: 23.6 per cent
Soul ballad (79 BPM, Adele, ‘Hello’) duration: 15.3 per cent of playlist
Range expenditure of the 22.48 miles attributable to soul ballad music: 13.3 per cent
"Kia UK recruited Dr. Duncan Williams, a lecturer at the University of Salford’s School of Science, Engineering and Environment, and co-founded WaveTrace, a psychoacoustic consultancy that observes how humans react to auditory stimuli, to help conduct their experiment. The company wanted to see how music choice would impact the real-world range of the Kia EV6, which can get an estimated 328 miles to a charge on the WLTP combined cycle.

It’s worth noting here that the WLTP cycle isn’t the most accurate reflection of real-world range in the first place, since it doesn’t test EVs in variable weather conditions; final range estimates tend to be more generous via the WLTP than via the EPA. However, because this study compares the differences between music choices, the overall WTLP range figure is less important than the real-world ranges that were discovered during testing. It’s just a nice starting figure to work from.

To conduct this test, participants who had never before driven an EV got behind the wheel of the EV6 in the GT-Line S trim, since that has the most powerful speaker system of all the trims. Those drivers were provided with a fixed playlist and outfitted with a device that recorded their biometric measurements, including skin temperature, sweat, pulse, and heart rate variability. Then, they were sent off on an 18-mile route."