As you said, he’s disabled. I have a trisomic uncle and I would’ve understood if he was put on a leash (he wasn’t, he just listened to my grandpa, but not everyone has it so easy). I don’t understand the need for it in other cases. I mean, two of my friends’ kids are runners and all we do is just run with them and grab them when the time is done, they/we have never had any need for a leash. I’m sorry if people have harassed you about it though, I certainly wouldn’t. I just voice my questions and opinions in voluntarily attended online spaces.