Yes, aging is accurate if you create multiple invoices, but that is not a good workaround. Here's a real life scenario.
My private school client bills for tuition. It can be paid immediately, or in two, four or ten installments. They also credit for scholarship grants and for loans, using the same payment plan as that selected for tuition. There are added complications, but let's leave it at that.
A family with two students enrolls, chooses the ten installment plan, and is granted a scholarship and a loan. Under your multiple invoice scenario, 10 invoices and 20 credit notes must be created. Not a big deal, the copy feature works OK.
Before the school year starts, one of the siblings drops out, forfeiting the deposit. All 30 transactions must be adjusted.
A month later, the family decides to switch to paying under a four installment plan. All 30 transactions must be zeroed out, and 12 new ones created.
Assuming the AR clerk knows what to do and is accurate, we are still looking at a daunting task, for what should really by quite simple. And this is not a far-fetched scenario - out of a school with 300 billing units, approximately 20 end up making these kinds of changes. And this doesn't even count last minute adjustments to scholarship grants and loans.
Multiple invoices is not a workable solution in most cases.