This is a huge can Of Worms around here
My Ds has a "back pack" that just happens to have a leash that clips on and off. He loooves it
. Until he is satisfied to hold my hand and not run into the busy street that we live on the corner of, we will use it to go for walks.
When my sister was little and I was her 18 y.o. nanny, we had "sister bracelets" (two velcro rings with a stretchy cord in between) so that she wouldn't lose me in a crowd. No stigma and she never had to be forced or coerced into wearing them.
IMHO any safety device can be used in a respectful or disrespectful manner.
If this were a poll I would vote only appropriate in certain situations.