And what happens once discarded gene-editing technology is available to 14-year olds? There are few technologies in history, including nuclear, that haven't eventually been available to curious teenagers.
...because the world has been ended by kids making their own nuclear weapons? What?
Backyard nuclear devices don't end the world, but can still cause a lot of harm. Superdiseases made in a garage might one day have civilization-crippling consequences.
Top scientists would struggle to create a super disease today. Worrying that a kid will do it when the technology is commoditized is putting the cart well before the horse.