The "go, just be careful" advice I gave for Rio applies to many places, but is not absolutely universal.
A rather ambitious friend was planning a trip to Honduras around ten years ago
and I sought the advice of another friend who had actually contributed to travel guides to much of Latin American (and is himself Colombian).
His advice was not to go.
"Do you mean that, or do you mean it's ok to go if you avoid certain places and are very careful?" I asked.
His expert advice was
"No. Really do NOT go. Even people who are from Honduras and have relatives there mostly don't go. Do not go, period". (this was around 2011)
So places can get too dangerous to visit. But Rio is not such a place, nor was it at any point in recent memory.