It just changes the rules to treat handguns like long guns when it comes to teaching your child to shoot, like every other state (AFAIK) treats them.
And if a law is too stupid to enforce, it should be repealed, or else you create disrespect for the law. Saying that parents could legally allow their child to shoot a 12-gauge (.729 caliber) shotgun or a high-powered .30-06 rifle under their direct supervision, but not a .22 pistol, was asinine. And misuse of guns by children, as well as allowing unsupervised access to children, is strongly addressed by other laws, not this one.
"But kids often shoot people by accident"
Not under their parents' direct supervision, they don't. Most "child with gun" incidents are when a very young or untrained child finds an unsecured gun when their parents aren't around, not when their parents are teaching them to shoot. And teaching your kids gun safety actually makes that kind of thing less likely, not more. Just like teaching your kids to swim makes them
less likely to drown, and teaching them how to safely build, manage, and extinguish a campfire makes it
less likely that they'll accidentally start a house fire and burn your house down.
Gun safety is a learned behavior, and is not well served by "abstinence only" education.