If a homeless person walks up to you and aggressively threatens you as you are passing by, no crime has occurred. But if you're an SF native, you've learned to shrug it off as a commonplace occurrence. You've learned to become thick skinned towards these incidences. And when a real crime has happened, you'd likely assign more gravitas to it.
This is why there is a disconnect between numbers and quoted statistics and how people feel.
Depending on what they say, isn't that still technically "assault"? Or "disturbing the peace"?
Also, if there's poop all over the sidewalks, those are all crimes too.
The problem is that all these petty crimes are generally never reported, and certainly not acted upon by police. So they never show up in the crime statistics.
There's a disconnect between the numbers and quoted statistics and reality, because the statistics come from the police, and their reporting isn't accurate. It isn't accurate anywhere of course, because police aren't perfect and many crimes go unreported for various reasons, but to SF natives, it may seem that this is worse in SF than other places, or in SF in earlier times.
Some guy / lady yelled at you for 10 seconds aggressively. Are you now going to call the cops / file a police report?
I think a majority of people would just move on with their day. So yes, to your point, this wouldn't show up in any statistics.