I don't think anyone should be assessing themselves by weight, muscle weighs a lot more than fat, hence why overweight is an incorrect term, body builders are extremely overweight, but that doesn't mean they have excess fat just because they're heavy.
Telling people what the ideal weight should be is even more harmful - a lot of anorexic people have weight issues as opposed to size issues (i.e they find it harder to allow weight gain, even if their shape/size remains unchanged), wishing they were lighter because everyone is told that heavy=fat.