Not sure where I read it and I think it was 2015 to 2017 that the nissan qashqai was motability most popular car.
I know it’s not what you asked but may be of interest. the lastest figures from Motability:
112,376 scheme cars registered so far in 2019
19,793 scheme cars registered June 2019
8.86% of uk registered cars were scheme cars in June 2019
not sure how to go about getting most popular cars on scheme, maybe @WMCForum knows some source ?