My thought as well, the video Tom Scott did on the mountain town that has bespoke electric vehicles (and strict usage on them for needed business) comes to mind (R2oD1ZHNMFE). I don't know how much is law and how much is companies not caring to cater to that market (even with designs that they sell in Europe), but Kei-like vehicles can still be affordable without being fully unsafe (but the issue of safety is more about the market making larger-and-larger trucks and SUVs, and lack of viable car alternatives paired with high speed limits).
Higher cost really is not a fix. Other concerns like privacy seem like policy could mesh well with low-end (no internet connection, just-a-radio, common off-the-shelf parts, standards+no DRM etc). It would be nice for the option to exist in this space that US car companies are not trying to fill anyway.