Well, I am in my 60s now, so it is a bit late if IABU! As children we went every 6 months, but I am not sure why. It was expected back then.
In the last 40 years I have been twice, both times because of side effects of other non-dental treatments.
The dentist I saw last year, to get a clean bill of health before starting on a powerful drug, now wants me to come back, as it is 6 months since I last went, and this is seen as enough justification to try and insist I go again.
I have never had any problems with my teeth, and generally go to the dentist once every 20 years or so.
I am a teacher, when it comes up in lesson, have asked my classes about their experience of dentists - I would say most teenagers these days have never seen a dentist, and don't have toothache.
AIBU to think the need for a six month check up is a myth? And if it aint broke, don't fix it?
I would go it I had a problem, or toothache.