I'm always bemused by these comments of big foreign money/big immigration coming in to save real estate prices. Some people think the US is some kind of revolving door and any warm body can just come over here and scoop up some property and live here. Emigrating to another country is a long, HARD, arduous process (remember 9/11? kinda changed things a bit in that regard), and frankly people just don't go "oh I'll just pack and move away from my family/business/job/culture because real estate prices are 30% lower there". As a Canadian working here, practically a sister country of the US, it still wasn't all that straightforward to just come in and work and settle here. There are formalities involved, credit ratings don't transfer, etc. etc. I can imagine how much harder it is for someone coming in from Asia. Plus emigrating anywhere you always lose something in the process (no right to vote/take part in politics, adaptation required/ must rebuild credit, levees/taxes incurred if transferring investments).
Of course maybe there's some golden tickets for very rich individuals where these rules don't apply. But then you're not talking about measly 1mil$ properties. It's not uncommon for asians to share an apartment for multiple generations so they can afford it, so the "big money" affording those 1mil high rise apartments could just be 5-6 people on lower incomes.