This is assuming oil is still valuable in the future in the face of increasing pollution standards, potential carbon taxes, and the rise of cheaper renewable energy production.

Oil will be a valuable feedstock for the forseeable future. Look at all the plastic in your house, in your clothes, in your car, wrapping your food, coating your circuit boards, the list goes on. Yeah, that's oil. Shame we can't harvest the plastic from the oceans and reformulate it into something useful.

Why not?

I haven't run the numbers, but seriously doubt it is economically viable. Most of the ocean plastic is small particles and it'd have to be collected, filtered and dried first.

Those first two can be done passively, or on the go with solar power.

Diesel and jet fuel by themselves account for over 30% of global oil consumption. Even if we get all other vehicles running on something else (ha), big trucks, freight planes and air travel will be guzzling oil for probably as long as we still have some left.

But oil products can be produced from biomass and energy too. And is carbon neutral, and doesn't have the potential side effects of extraction leaks and fracking concerns.

Oil isn't magic, it is straight up organic buildup put under heat and/or pressure. You can make 'fossil fuels' out of trees, grass, frogs, people, ect. It is just limited by our ability to produce energy which is currently our biggest restriction on pretty much every industry in the world and is what we are most concerned about solving.

"Last to run out" makes it sound like oil will be increasingly valuable as time goes on. What if you leave yours in the ground, and eventually it is worth almost nothing, because the world has moved on?

Oil has much greater economic value when used as a feedstock for non-fuel purposes. It is almost certainly a better idea to let any reserves you possibly can stay in the ground for as long as possible, and let everyone else sell theirs for cheap first.

But if 90% of the demand for oil (transportation) disappears and supply stays the same, the price is going to drop big time.

If demand dropped, initially supply would drop offline as prices could no longer support the more difficult wells rather quickly. And as actual production falls, the amount charged that the market could bear (if the market was mostly the non-fuel, high-value uses) could be significantly higher than what we see today. A scary time to be an investor in an oil company, absolutely. But taken in the broad view, leaving oil for later will almost certainly enhance total future potential profits, if not the rate of profit per unit time.

Good, that's even better.