Which will never happen because you’d have to rip up cities and replan them.
But whatever I’m sure your gonna say it’s a “matter of resource distribution” not a space problem but I’ll just say this, we will never solve the distro problem because of greed.
Plus every new person born is gonna generate a shit ton of carbon. They’re gonna need a place to live. That’s space that used to be an ecosystem.
So idk maybe you want the planet to be turned into Courascant (one big planet sized city). Sure there’s space for trillions of humans if we stack em up high! Good luck feeding them.