You are still focussing only on the acquisition cost of EVs, it's the cost of ownership that is important, even for those with little means. The cost of motoring has steadily tracked inflation for most of the last few decades, except in some areas, environmental penalties are pushing cost higher than that. So far we've seen Euro 3 diesels either attract penalty charges or in some case banned from certain areas. This will accelerate sharplybrcause:
1) as a genuine attempt to reduce pollution and CO2 emissions
and
2) as a tool to remove ICVs from roads as part of decarbonisation policy, (with a byproduct being that 1) above is easier to achieve
So the 'cheap' secondhand EV runaround will become more expensive to buy but have much lower running costs, a longer life and greater flexibility in road access (as the ICV will at the same time be more restricted). Once the process really starts to bite, there will be a rapid loss of interest in polluting older vehicles with ever tightening restrictions on where they can go.