If nuclear fusion takes off, we have more power then we ever need, and mass pumping Co2 out of the atmosphere could be a viable thing suddenly.
Then there are looming miracles in food production. Lab grown meat and indoor farming in high rise buildings could massively raise food supply.
And lastly, autonomous robots doing construction & logistic work, and beyond that replacing basically every heavy lifting job on the planet. There are ~50 millions or so car produced annually, what if we started to pump these kind of numbers in robots? There could be "landscaping projects".
Throw all these technologies together and earth might look like Coruscant sooner then we think.