This is actually not an attack on personal trainers.
Recently I have had several people at the Golds gym I attend ask me for advice/tips for front squats, back squats, and olympic lifts, as I am one of the few people there that do them constantly.
One of the trainers saw me helping someone on cleans, and came over after we were finished. I expected to get yelled at for teaching such a “dangerous” lift. Much to my surprise, he merely complimented me on taking the time to help people, and asked if I would be willing to teach him how to clean and snatch. I have even seen him deadlift before.