You are right to be skeptical, 30lbs is not the all-up weight of batteries as there is a case, bms, wires, plate, thermal silicon sheets. The all-up weight of the 1-hour pack is just about 38lbs (4kwh pack), dropping down to the 2kwh pack knocks off about 15lbs but there is still the weight of the other components other than just the cells.
Ya 30lbs pack giving 1 hour flight time would be incredible, either a very efficient motor/flying like cruising at 3kw or very energy-dense battery. I think we will see it at some point but not in the next few years.