It's not true that if you are poor in a third world country, you cannot afford a vehucle. A lot of poor people in third world countries instead use and indeed share incredibly old cars from the 60s-70s, or motorcycles. It is often literally a matter of life and death - if you get stung by a scorpion in the Atlas mountains, unless your family or village have a car and fuel for it, you're just not getting medical care, which is why you'll see many such very old cars there. This is a real issue - the micro-village in the mountains where part of my family lives had one of my aunts die as a baby because a scorpion bit her and she couldn't be brought to a hospital due to a lack of transportation. They bought a Citroën 2CV after, and it's still used up to this day.
Now, of course, like all non-progressive subsidies, they benefit the wealthy disproportionately, because they make disproportionate amounts of money. But for the bottom 20%, those 7% of the subsidies are a lot, because they often make less than 7% of the income.
So a workable solution would be to make these subsidies progressive, tied to income and consumption, but unless you've lived there it's difficult to understand just how bad removing them altogether would be. It could literally lead to revolts.
Also, that study is hugely problematic because it takes the entirety of the world together, instead of operating at national scales. I already agreed that for richer countries this should be phased out, and subsidies are likely to be much higher in richer, often non-producing countries, than in poor countries.
Also, before they got solar panels and batteries around 8 years ago, they were still reliant on kerosene for lighting.