I was there a few months ago. Don't remember seeing any litter and didn't feel like I might get jacked, no more than what you would living in any larger city.
I think especially when it comes to your sense of safety it's mostly the dangers you're familiar with versus unfamiliar.
It's like how we have threads about pickpockets and Europeans don't understand that it's basically a non-existent crime in most of the US. Likewise you have different scams and grifts in different parts of the world.