As has been said many times, it’s much easier to let your child order something that they’ll definitely like and try to get them to sample something interesting you ordered, than to force parents into forcing their kids to order/eat from the main menu. When my kids were little, the oldest ordered off the kids menu until she was like 16, the middle one started off the real menu by the time she was 8, and the youngest had a bunch of allergies so often wound up with (very good) special-order chicken fingers. I fail to see how that affected other diners.
Don’t forget why don’t authentic Mexican restaurants serve queso dip?