Earlier quoted context omitted.
people with dogs off-leash are extremely inconsiderate. they're also the type to get hostile and even violent if you say anything
I frequently walk my dogs without leash. They follow my command, don't disturb other people or dogs unless both parties engage and generally I don't do anything that someone who has a leash wouldn't be doing. They also walk side-by-side with me when off-leash. This is very common in the city I live and surrounding area (Barcelona, Spain and Catalunya). Both me and others without leashes are indistinctive from people…
That's great, as it should be. However, the majority of dog owners I encounter are at the mercy of their dogs, they treat the dogs not as dogs but as humans and try to bargain with them. This is merely annoying when the dogs is a golden lab, but can be mortal when it is a "sweet" "rescue" pit.
You are right though, it doesn't matter if the dog is on a leash because people also get these 30ft (10m) leashes and all of a sudden, out of nowhere, someone's dog is trying to "just show affection" to a toddler.
So, the golden rule is not to get a dog if you can't be pack leader. A very bad proxy for a person being able to control a dog is the dog being on a "short leash"[1]. So, people go for that rule.
Then you get the 100 lb jogger (45 kg) who attaches a Doberman with a breakaway clip to their shorts.