To have economic growth, you have to actually grow the amount of trade being done. Can't see how you could do that forever - despite the best efforts of advertisers and companies engaging in planned obsolescence, who are largely responsible for the climate shitshow, people will at some point hit a consumption limit. You can play accounting tricks on GDP to some extent, but I'm not convinced this is enough. If value becomes completely detached from reality, people may lose faith in money, and the whole thing will just crash and burn.

Or simply reach peak population growth which is a common occurrence on the small scale. With population at a steady state, there is nothing GDP needs to outgrow.