~30% of the homeless population. I agree that many of them (most?) suffer from mental illnesses or drug addictions, and that the liberal policies from City Hall are addressing symptoms more than causes.

Source: https://ncg.org/sites/default/files/resources/Tipping%20Point%20-%20Reducing%20Chronic%20Homelessness%20in%20SF.pdf, which cites data from a number of places.

The rest of them, the 70% that experience episodic homelessness, are in a different camp. And you bet that they are affected by the increase in housing prices driven by the housing crisis. The numbers in SF, last I checked, were something like 400k jobs created in the last 10 years, and 60k housing units built. Evictions are not uncommon for low-income residents.

Whatever measures we think will address that 30% will not magically get the other 70% able to afford a 3.6k 1-bedroom apartment.

I work in downtown San Francisco, and the majority of the homeless I encounter are there due to either mental illness or drug addiction.

I used to live in the city, and still go there often. I'm familiar with the situation. Not just around Bart (Civic Center especially) and in the Tenderloin, but also in other areas in the city like the area near Alamo Square. You also see that in plenty of other places in the Bay Area, including a stretch of El Camino Real in Palo Alto where some Stanford nurses live out of RVs because they can't afford rent. My ward in the city had homeless members, converts, and investigators. The homeless you see during your commute are not representative of all homeless in the city.

People rioting about gentrification and tech growth are barking up the wrong tree.

I never mentioned gentrification. If you think soaring rents due to zoning regulations and economic growth that has brought a lot of high-income residents to SF and Seattle have nothing to do with some people being unable to afford housing, don't know what to tell you.