They are trying to lead the user in determining whether the missed RMD is subject to a 25% excise tax (not corrected during the correction period) or instead to a 10% excise tax (the RMD taken late, during the correction period), changes brought about by the SECURE 2.0 Act becoming law. However, the penalty is assessed on the aggregate amount subject to the 25% excise tax and the aggregate amount subject to the 10% excise tax, so trying to make the determination on a 1099-R-by-1099-R basis doesn't really work for IRAs and, separately, for 403(b)s, where RMDs can be aggregated and the total RMD taken from only one of each of these types of retirement accounts. To accommodate the cases where the RMD for one of these accounts is taken from another, the present implementation in TurboTax requires allocating the total RMD amount for one of these types to the different Forms 1099-R such that no entry of the required amount exceeds the gross-distribution amount (unless there actually has been a missed RMD, in which case it would make sense to allocate the missed amount to just one of the Forms 1099-R for that type of account (IRA or 403(b) of the individual).
