Right. This is a plausibly correct answer to the question originally posed. As much as we might like the answer to be "never," "never" is an incorrect answer.
Unfortunately it is also a rather pessimistic answer. Less frightening scenarios are possible, though perhaps not much more likely.
Populations are growing. Our consumption of fossil fuels is not abating. The supply of fossil fuels is dwindling. These trends will continue until the supply of fossil fuel is so depleted that we have to start using it a bit more carefully.
Unless we find another source of free energy, energy will become increasingly expensive. It does not look like we will. Nuclear proved to be much more expensive than advertised. Solar and wind are all well and good, but they will not supply enough energy that individual people can drive indiscriminately the way they do now. Driving will eventually become too expensive. Other modes of transportation will become more attractive, including bicycles.
I don't know when this will happen. Perhaps not in your lifetime. But if you think it will never happen, you are mistaken.
Yes, very well put and you expand on the sustainability crowd's favorite tautology: "If it can't last forever it won't last forever." Sometimes it's necessary to restate the obvious because people just don't get it.
Another version: "This party can't go on forever. Let's all go to Denny's for breakfast."
We must realize that inevitability is, um, inevitable. The gas will run out. The climate will change. The roads will get so congested that we can't go anywhere. The sooner we accept all this and start planning for it, the smoother it will go when it does happen. Making smart changes does not have to be the end of our economy or our way of life. But if we keep ignoring and denying the problems associated with cars, the worse the inevitable transition is going to be.