Probably because before reading the news, many people watch TV, but not all ordinary people are not interested in the author's biography, his education and work experience. And before going to the surgeon under the knife - they are very interested.
The death of one person is a tragedy, the death of 1000 people is statistics. A bad surgeon kills a few, it is a tragedy and he is quickly fired. A bad journalist kills millions, and these are statistics, they don't fire for that.
Bad work of a surgeon is easy to prove, bad work of a journalist is very difficult, and who cares.
By "kill or wound with the word" you probably mean ethically difficult situations, for example, the disclosure of some information that is killer news, but endangers the life or safety of people. It's hard to disagree with this, but on the other hand, how can specialized education help here? Most journalists by profession are quite ... mmm ... thick-skinned, to put it mildly. Here, except as your own conscience, will help little. Perhaps the "non-professionals" will do better with this.
Well, in general, a word can hardly kill or injure, but even if we assume that it is possible, this will not change the answer, because surgeons, as a rule, operate, and people without medical education have little problems with this :)