Citation needed. Your use of "genuinely" indicates to me that there's a large subjective component to that statistic. I'd believe that it's physically possible to replace 99% of "suburb and city traffic" with "trains, bikes, or legs." However, I'm not at all convinced that 99% does not "genuinely benefit" from cars. My guess is that such replacement probably requires a strong ideological commitment to car-disuse [1] in order to persevere in the face of real drawbacks.

[1] I know several people with such ideological commitments.