[TeMPOraL]

> The earth is a finite world, sustainable or not you won't be able to grow indefinitely.

It's not "indefinitely". It's just "long enough that we can bootstrap a space economy and expand into the Solar System", or alternatively "long enough so that we can fix the environmental damage, get rid of poverty and most diseases, and slowly S-curve the economy into some acceptable state". Or some combination of that.

Moreover, not all growth is tied to physical space and resource use. We're also not using the space and resources we have efficiently. There's plenty of room on Earth for us to grow, but it might start looking more like improving things than expanding them.

> if we go back that would impact the GDP.

Switching to a sustainable level of growth will require that - slowing down the growth itself, and even a temporary shrinking of the economy.