I have added clarifications in the original post. To be clear, this warning/error is only shown for e-filing NJ return AFTER importing 1099-B from Robinhood with tons of transactions. It has NOTHING to do with Schedule B. The reply from a TurboTax representative also mentioned that it is a concern with NJ-DOP.
Further, the root cause is likely because Robinhood stops reporting transactions as is (ONLY few sales actually from the user's perspective) but a breakdown of underlying transactions compared with 1099B in 2020. Nonetheless, as a PAID service, TurboTax should be able to aggregate as necessary instead of suddenly rejecting NJ e-filing AFTER a paid user imports a 1099-B with tons of transactions. While manual aggregation is possible, it makes little sense for a paid service to save no time or effort in the end but incur additional cost for paper printing and mailing.
