I'm not unfamiliar with the causes. It's a pet peeve precisely because I keep seeing it handled like this.
Yes, Japanese frequently does stuff like omitting objects. Writers can use that kind of thing for ambiguity, like here. They can do that because it doesn't sound weird in Japanese to talk like that. But, in English, it does. In English, there are different ways of preserving ambiguity. It's not always easy, and settles halfway with stilted language like "that person", but it's preferable to this.