My poor DS1 had (has) a terrible phobia of dogs that he's really only got over in the last year or so, and he's 17 and tbh, he's still jumpy around them ,just he's learned to disguise his fear.
I put it down to an incident in a local park when he was 2 ish in which an enormous dog ran out of nowhere, knocked him flat on his back and wouldn't get off. DS1 was hysterical, I was pulling and pushing at the dog to get it off, oh btw while also wearing DS2 in a sling which kind of added to the excitement
Then the owner, a large man, came over and started screaming and shouting at me for pushing his dog;
"which only wanted to play and people like me shouldn't bring our brats to the park."
It was very traumatic, luckily DS1 was completely unhurt other than scratches and bruises etc, well, physically at least , but as I said above has never got over it
I love dogs, trained dogs that is, and grew up with a beautiful lab that I miss to this day, and my younger three would probabaly love a dog but it would never have been fair to DS1 to get one.
I think dogs should be on leads unless the owner can guarantee they won't go out of control, jump up etc.
Anyway, I quite enjoyed that rant, its been cathartic