I mostly agree but I think we could maintain a lifestyle that is near Western levels, but done more efficiently. It wouldn’t be the same lifestyle, but it would be a good one.

I.e.

• dense, walkable neighbourhoods with mixed-use zoning
• trains, trams and electric buses instead of cars
• any job that can be done from home should be mandatory to do from home
• minimal to no meat consumption, especially emissions intensive meat like beef
• economic incentives and disincentives to minimise energy consumption and waste
• circular economies that re-use and recycle most things
• 100% renewable energy production (and eventually, green manufacturing).

Although even with that, it would be an easier job if there is some level of population decline, but I don’t think any encouragement is needed (societies where women are highly educated tend to have declining birth rates).