This is a risky reply as it could go well off topic;
Legislation and the goal for carbon neutrality will force it, not cost, at least not in our or a good few generations lifetimes. Look at how proven oil reserves have grown over time, exploration technology advances all of the time.
https://www.indexmundi.com/energy/?product=oil&graph=reserves
I agree sort of but, our choice is likely to ween us off it before cost becomes the most prohibitive issue.
The fact we know or constantly find more is a red herring, but in order to start the conversation you always need to ask the question (because there are some who thin the faster we extract the oil the faster the earth will make more, and you cant have sensible conversation with that)
So assuming you agree there is a finite amount, we just dont know what it is. We dont know what we dont know.
What we do know is that when you have a finite resource, using up that resource means you have less left.
Note I didn't say we would run out in x years, just eventually.
Then logically you will agree eventually that finite amount will be getting towards the point of running out, so it will become scarce and if we havent transitioned off or arent working towards that it will rapidly increase in cost as people get ever more desperate and willing to pay for the last bit.
I tend to think we would probably wipe out humans before that point, but its a bit mute since it wasn't my point and I think somewhat unrepresentative (by the other guy) to make out that using fuel for manufacturing somehow equates to usage.
We will use loads of products from petrochem to make sky boxes, we dont think we should fule them with petrochems as well
