Right, but you also don’t pay a penalty if you give the same $6500 to them out of your income or out of savings in a taxable account.
Also correct, but as you point out you are going to be paying the tax anyway. So once you have paid the tax anyway, there is no additional tax consequence to giving the kid the money to use to put into a Roth.
So this is where it gets very tricky. If you leave it in a 529, that untaxed growth can continue on indefinitely. As long as someone eventually uses it for qualified earnings, it will also never be taxed.
Of course Roths also have this feature, but if you can fund them out of taxable instead, you are then converting something that doesn’t have this feature into something that does.
OK, so IF you have $6500 sitting in a 529 (and it is eligible, which is tricky), and $6500 sitting in a taxable account after you paid taxes you were going to pay anyway, is it better to convert that to no more 529 and $6500 in the Roth, or no more taxable, $6500 in the 529, and $6500 in the Roth?
Not a question with an obvious universal answer.
I note the main scenario in which you would typically consider doing the 529 to Roth conversion would be if you actually needed to spend the $6500 in taxable. Like, you should probably pay your rent and utility bills first, if you need it for that. So if you simply do not have the excess income or taxable savings needed to help with the Roth contribution, and if by using the 529 the kid can make a Roth contribution they couldn’t make themselves (or get closer to the limit), then maybe that will make sense.
So I am sure some people will do it in some circumstances. But I also think many people will end up deciding not to.