As population growth flattens out, the demand for cars, homes and food will also will flatten. We've relied on our homes to provide for our comfort now, and in retirement, we'd use the equity. If demand is flat, I'd expect the value would remain unchanged.
This has all kinds of consequences... not the least of which the 6% charged by real estate agents to sell a house.
New innovative produces will see growth. Think cell phone 15 or 20 years ago. I'd expect the technologies that allow us to take advantage of wind and solar power will be growing for the foreseeable future.