Of course it would be! Fossil fuels are cheap and easy to extract. Energy consumption is directly correlated to quality of life. You think if there were fewer people they would just say "no thanks, we've had enough material wealth, just leave the cheap and easy energy in the ground, we're good"

What in our history makes you think our resource usage is related to population? You said it yourself that most of the world is living in poverty and needs to increase their resource consumption to get to a decent quality of life. That's clearly one of the things that would have happened with fewer people. The other would be whatever mega yachts would be if the rich were 4x richer..... Maybe space yachts.....

This anti-natalism thing you've got going is really rotting your mind.