Can I ask why you feel that public transit is unsafe in the US?
https://en.wikipedia.org/wiki/Killing_of_Debrina_Kawam
https://en.wikipedia.org/wiki/Killing_of_Iryna_Zarutska
https://www.cbsnews.com/newyork/news/nypd-men-pushed-subway-...
Many more such cases occur and aren’t widely reported. I’ve personally witnessed a stabbing on a bus
My chances of being stabbed inside my car are much lower
You might not get stabbed, but driving is incredibly dangerous. Even just in terms of violence: road rage is tolerated to a large extent in America. The difference is that the news doesn't report even a small fraction of the traffic deaths in this country. In Iowa, the state I used to live in, around 300 people died every year from driving. I don't know a single one of those people despite their death being a tragedy. Whereas the stories you linked were broadcast coast to coast.
But I am in no way stopping you. Feel free to take USA public transit, and (i truly do not know how) look your family in the eyes and encourage them to do the same. I truly hope that I do not read about your or your family in the news in this light (nobody deserves that), but your chances will be higher than mine.
I get what you're saying. The empirical evidence just doesn't agree AFAIK.