There is a degree to which people who have pets assume that everyone should react to animals the way that they do. If someone's dog jumps on its owner, they often react positively, rather than negatively. (In my case, the reaction would instead be "I have serious allergies and do not wish to have an unpleasant allergic reaction for the rest of the day".)

Some dog owners (to be clear, some, not by any means all, but it only takes some to affect other people's general perceptions) seem to think they are objectively correct and the people who do not want that are wrong. So it is not hard for me to imagine someone who finds themselves regularly having unpleasant interactions with dogs feeling like "dog owners should stop that from happening", rather than (as is sometimes the case) acting like there's something wrong with people who think it's a problem. Conversely, it is understandable how people who are close to and friendly with an animal all day will sometimes fail to have sufficient perspective-taking to realize that not everyone feels as they do.

I've personally never had the extremely unpleasant experience of having a large dog try to jump at me. I have on rare occasions had the experience of having a small dog run at my legs, and the owner not immediately treat that as a failure on their part, which was unpleasant. Fortunately, most of those have then had the "I'm so sorry" reaction, rather than reacting with indignance, but I've definitely encountered pet owners who projected indignance that you don't think their animal is a precious sweetums who can do no wrong.

If dog owner is scared, dog will try to protect its owner. I understand that part, but I do not get why they would release dog in such situation.

I understand people get scared, and do not control their emotion. But dog owner should still control their dog! Releasing dog after owner triggers it, is just pure hate!

It is like inviting delivery driver to your house, and latter claiming it was trespass!