My wifes family and relatives often leave food out overnight. I think the chance is there for bacteria to grow but doesn't necessarily mean it will. Leaving cooked chicken out is probably safer than leaving raw chicken out and then cooking it.
Look at the fresh markets where the meat is just left out in the heat. They don't seem to have too much problems from that either.
I know I was raised being told don't give dogs bones it will kill them. When I first retired here I would tell people they were going to kill their dogs giving them bones. They would just give me funny looks. After a short period I realised there are millions of dogs eating bones, of every type, everyday here and they aren't all dying. So while there may be a chance of a bone hurting a dog it doesn't happen that often.
Same with leaving food out.