In DTLA alone, we have foreign investment (mostly Chinese and Taiwanese) to thank for the construction of nearly 2,000 new apartment units over the past 3 years (including units still under construction), with an additional 2,000 apartments and 1,000 condos planned over the next 5 years.
DTLA has a less than 3% vacancy rate for apartments, and for 11 months out of last year there were fewer than 5 condos for sale downtown, so occupancy is not a problem.
My point was that foreign investment can help solve the problem, which supplements the post that I was replying to.
Also, I'm not sure what the point of your link was. London's housing market has little in common with SF's; housing-wise London's market is most like Manhattan. Wealthy foreigners frequently acquire London flats without the intention to live in them beyond a few weeks or days each year and primarily use the real estate as a way to store their wealth. London allows, and even encourages, uber-expensive housing developments that displace impoverished communities precisely to attract this type of foreign wealth. In DTLA, foreign investment under the EB-5 Visa program has been used to increase the supply of housing and non-industrial commercial usage in a space that historically had limited amounts of both.
