You're correct. I guess they're comparing against compressed pngs. Judging from the image at least.
But still, I think they're cherry picking one of the worst formats to make the comparison look good.
Not to say that means this is bad. Just the cost/benefit is not nearly as good as it appears. We need comparisons against ETC or DXT.
Big tax incentives for business to buy ev's - 2% Vs 30% tax as a 'benefit in kind'. The two Tesla drivers I know both bought through their business and then gave it to themselves as a company perk.
However, Britain must try harder here. Other EVs are available.