I think "hacker" is just one of those words that got used differently by the media and the public than by the people who actually knew anything about it.
That caused most people to think of "digital burglar" when they hear "hacker". And that made the "ethical" prefix necessary.
You can try to fight such a use, if you feel it's worth the energy trying to convince millions of people who don't really care enough to listen, but I don't recommend it.
What does your grandma thinks a "pen tester" is?
Gergely Polonkai
You have to believe in things that are not true. How else would they become?
Back in the 90s there was a separate term for black hat hackers: “cracker”. I used to like it and used it a lot. Nowadays we may want to use those hat colours (even though i never wear a hat).