There's no reason to separate cars from trucks and buses. Everything is getting electrified. In jurisdictions where Buy America Act doesn't apply (i.e. the world outside the US), electric buses are already the default.

Moreover, it takes a lot of oil to refine and transport oil. If there's no demand for road transport, then the corresponding demand for refining and transport will disappear as well.

Finally, coal is already replacing oil in the chemical industry. Not because it's cleaner, but because it's cheaper and more available.

About 6% is for plastics. That isn't going away anytime soon, but it also doesn't release much carbon, it's mostly just changing form from liquid to solid.

You mean a good amount of the 46% consumed by road transports. So my napkin says, when we all switch to driving EV the oil demand will drop by 15%. It's something for sure, but not overly dramatic (to me).