There is no way that knowledge is bad for us. None. There is no such as "ignorance is bliss". That's only a saying!
Look at the educational work done by the Brady and other anti-gun people. Depending on the spin you put on information, it can be bad or good.
I could go on as well...give me an example of just one professional who's job affects your everyday life that you DO NOT think needs mandatory training; your doctor? your attorney? your dentist? how about your CPA?
The guy who built all the cabinets in my home has no mandatory or formal training. Beautiful work, BTW.
I know musicians who have never had a music class.
My father grew up hunting for the family. He never had a day of training with firearms until he became a cop.
Like the OP, I have been dismayed by the folks who show up to renew their CHLs and unload the ammo from their guns that they loaded into their guns after qualifying 5 years before that, not having shot their guns, cleaning, lubed, or anything else in 5 years. They shoot, pass the quals, and load up the same defense ammo they unloaded and I am confident it will remain in their guns until they renew in the future.
So the folks are fairly ignorant about their guns. Their guns do not affect their everyday life. In fact, it seems the only things their guns really affect is one day every 5 years.
Yeah, a lot of professional who do things that affect our lives have had formal training. In no case is that training constitutionally required.
Oh and speaking of cops, they have had formal gun training, would you say they are all highly skilled shooters?
Education may give people some knowledge, but it doesn't necessarily make them smarter.