I would say that, yes, the San Francisco area of Panama City is pretty safe. When walking around at midnight, I would be, like everywhere in the world, more cautious, but overall, it is safe.
In order to be safe, I would try not to walk in certain areas, and l would rather be close to residential places in San Francisco like Coco del Mar or an area like that, which are rated upper class places in San Francisco. I would be rather safe walking around at whatever time.
I would say there is a little part of the San Francisco area of Panama City that is a little older and might be considered less safe. Most of the San Francisco area has been developing over the last years and therefore is safer now, but even the old part is still really safe.
Maybe 50% of the people in San Francisco have bars on their doors and windows, but they are there more as a decoration than for safety reasons.