The population of a place doesn't have to double, or even change at all, for prices to go up. All that is necessary is for more people to want to live in a place. Those with the $ to satisfy that desire will outbid those who don't and you can easily double/triple/10x prices with no change in population.
How come more people want to live in the entire US if the population is relatively flat? Prices are up everywhere.
The only answer is that the increased observed demand is a result of the increased investment demand (rather than native demand)
Your factual statements are wrong. The US population isn't flat over time, and housing (supply) decays over time. Prices aren't up everywhere, just the places people actually want to live.
Let’s see some data:
https://jabberwocking.com/we-dont-have-a-housing-shortage/
Housing construction exceeds the population growth for the past 20 years. But housing prices are skyrocketing especially the last 10 years.
Your figure doesn't contradict my claim. We have spare housing capacity in undesirable places people don't want to live (rural towns, small midwest cities). We have shortages in the (especially coastal) cities, where the jobs are. This is obvious from prices, which are set by supply and demand.
https://pbs.twimg.com/media/Gw_BQYXbUAEicud?format=jpg&name=...