Earlier quoted context omitted.
So you think anyone should be able to call themselves "physicians" or "lawyers" or "police", as those are English words that predate their professional associations?
The problem is that there are a small, specialized clique of Engineers who have professional certification, and a huge population of engineers who don't have this certification and are not required to have it. The boundary between the two groups is fuzzy and a bit contentious, with each side seeking to expand their domain. There's no such confusion when it comes to the other professions listed, no huge gray area wher…
Just an aside, but that is a gigantic undersell of veterinarians. The difficulties of becoming one aside, just seeing that "humans-only" doctors only work on one kind of ape, compared to the many very different kinds of life forms a veterinarian has to deal with (of course they specialize too), I don't understand why one would think a veterinarian would deserve the word "only".