It’s another example of unintentional bias at play. Most “Googlers” living in safe, well-maintained suburban USA assuming the rest of the world is the same.
Anybody living on the Bay Area is painfully well aware that there are seriously sketchy neighborhoods. It's probably more an issue of data: there are no street-by-street crime maps for most of the world, and neither can Google feasibly collect this on their own.
They absolutely could make a "safe zone" map overlay, but the political consequences would be PR suicide.
While I agree with the sentiment, that's a complex problem to solve, what streets are "dangerous" and what aren't. Especially at scale.