It’s great that you are admitting you are wrong, but I see a strong pattern in this post of not taking the time to think about or analyze the issues you are talking about.
This is not a quality that is desirable for someone charged with helping to run a huge city with incredibly complex challenges in housing, transportation, and police reform, among other things.
If I were to write an op-ed column, I’d make sure that all of my points can’t be debunked with a cursory look. Maybe you should do the same in the future.
For specific things, as the other poster said, temporary parking structures? Structures that hold hundreds of thousands of pounds of weight typically aren’t temporary. Parking garages must be built much sturdier than regular buildings due to the weight they hold. That’s why they are massive reinforced concrete. They also need ramps (which would have to be removed).
This means that it makes utterly no sense to build parking garages to later turn into housing. It would be cheaper just to tear the whole structure down. Did you even think about this idea for 30 seconds, or consult a structural engineer, before putting it out to the entire readership of a huge newspaper?
Lastly, this is San Francisco. There isn’t much spare land around, and dedicating more of it to store automobiles is silly. How would you pay for this? Where would you put it? You would need to demolish other buildings. Also, how do you justify having the government subsidize parking, when most of the elderly you are purporting to help can’t afford cars? Why not just cut to the chase and build housing in the first place.