The challenge is that 5150 holds are:
1) very temporary ‘fixes’ to what are almost always conditions caused by some kind of chronic situation - often bad environments, toxic families, serious psychiatric and drug problems, major life events which don’t just go away, ongoing manipulation or emotional abuse by someone near the person, etc. often many of these things all at once.
2) very traumatizing on their own with severe long term legal and monetary consequences. Practically speaking, people lose a significant amount of rights they never get back (including the right to own firearms [https://www.atf.gov/file/58791/download], the right to adopt kids, hold many jobs, etc.) the moment they get a 5150. Getting a 5150 is one of the few ways one could lose custody of their child for good, at least in California. If someone has a legitimate history of psychosis or other serious mental health conditions, that’s all probably a good idea and legitimate! there is also a history of abusive folks using things like 5150’s to abuse and target folks they are trying to control (like abusive parents, ex spouses, etc).
Getting thrown in a psychiatric hospital against one’s will is not a pleasant or comfortable situation for anyone, let alone someone going through a psychotic episode. But the best society has come up with so far, and definitely better than them stabbing random strangers on the street (or themselves), or being thrown in genpop. Usually, anyway.
It’s a short term ‘fix’ for what is often (but not always!) a serious long term problem. Which is better than nothing!
Emergency and Long term involuntary commitment has a long and storied history of being seriously abused to steal people’s assets and manipulate/control folks who clearly were not crazy or a danger to themselves or others by any real definition.
It’s also a necessary tool when attempting to manage serious mental health issues in the population.
In both of these cases though, do you really want to set the bar so that it doesn’t require a clear, documented by a third party and actual/present danger to someone before it gets used?
Because I guarantee if you do, it will be used by angry spouses, controlling parents, political/business opponents or leaders, etc. against sane people all the time. More than it already is, anyway.
Which is often.
SF has a serious problem. Actually using 5150’s more isn’t likely to help though as most of the people getting them likely already have gotten them before. It’s a revolving door.
They get screwed up enough to warrant an emergency hold. They get help, temporarily stabilize, and within a week are back to the same situation. Eventually, they go psychotic again, and rinse repeat until they die or figure out how to get out of the cycle. Many die.