They tend to be in much lower insurance bands and tend to incurr significantly lower motor tax - comprehensive policies for EVs are higher due to the (current) dearth of parts and licensed repair centres versus ICE cars running on multi-year platforms or sharing parts across lines that share a single monocoque design (e.g. VW, Ford, Toyota versus Tesla and their publicised parts shortages).

The problem is that, for economy of scale reasons, Comprehensive insurance is often cheaper than third-party cover in the UK, despite people tending to never claim so as to keep their no-claims bonus and not spike their premium out of affordability. With 3rd Party the EV option would be cheaper as they tend to be involved in less accidents, and when they do they tend to dissipate more impact on their side due to more modern crumple-zones and safety features.