I have lived in SF my whole life.
It's not that anything specific has changed in SF - it's more a case of, the political machine has been running very smoothly in a way that does little to help anyone in particular, and occasionally it manifests as an "oopsie we let someone die".
The designated narrative role of SF since the 70's, as a Democratic Party stronghold, is to be praised from the left for progressive policies, and pilloried from the right for being a failing dystopia. And the narrative has simply intensified both ways over time, while the actual ground level conditions are way more varied. There used to be more overt violence, gang shootings and the like. Now it's mostly drug use and property crime. Mostly. After all, someone did just get stabbed. But in any case, the existence of the narrative allows every concrete fact to be shouted over by paid advocates for some cause.
To get at the truth you have to dig into the details neighborhood by neighborhood, department by department, year by year. The problems are not something that manifests from electing one wrong leader or voting yes on one wrong ballot proposition, but from the city openly allowing itself to court a menagerie of institutions that do no good other than to allow money to be shuffled between bank accounts. There are nice neighborhoods, mostly on the west side of the city, where if anything bad is happening, it's kept tucked out of sight. But go downtown and you get the apocalyptic scenes, which are supported by this "NGO industrial complex".
For one example, I present Urban Alchemy. Urban Alchemy describes itself like this:
We’re a social enterprise that engages with situations where extreme poverty meets homelessness, mental illness and addiction.
When a neighborhood, street or intersection earns a reputation as a place to avoid, we turn it around. Urban Alchemy is a peaceful and supportive presence, inviting communities to rebuild and restore a sense of pride and respect in urban spaces.
UA has a logo that looks like a cult symbol, and they hire former prisoners as "ambassadors"(i.e. they beat up and harass people, mostly homeless). This does nothing to fix the visible drug use problem next door to their building, of course. It would not surprise me to learn that UA itself has drug addicts in its ranks.
In essence, they seem to be doing the kind of thing you would expect the police to be doing, but the police aren't doing it, so they're going to do it very badly and say it is helping. What are the police doing? Not a whole lot, it seems. They were very happy to say it was the progressive district attorney making things unsafe. But even if that were the case, they just haven't been enforcing, not even traffic. They weren't defunded at all. After Covid, people started speeding around the empty streets and they didn't stop even after traffic picked up again. They need to fire the department and start over, like what happened in Georgia in 2004.
Tech actually did a measure of good for the city, at the expense of making it a really expensive place to live and bringing in a highly transient population of tech workers who "put in a few years" for a career launchpad. The tech companies threw their weight around and got some things built. However, a lot of the surplus funds that went into the government went into "programs" of the Urban Alchemy sort, and tech workers weren't in it for the long term and voted with the national narratives, not for direct investment in the neighborhoods. So, mostly, measures that favored landowners under progressive guises passed.
And that brings us to today, where it might actually come to pass that the city has to cut something for once. But they've made so many things in the budget earmarked that it'll probably be the wrong things that get cut first.