Actually, as your next post makes clear, the new LHA-6 (America-class) gives up the well deck to add aviation space. It's not just Dave B - it's the CH-53K and V-22 as well.
(1) No room for both well deck and full length hangar deck on same boat, even with 50K tons displacement;
(2) Sea surface amphib. assault operations conflict with rotary wing ops from same ship -- prefer to launch V-22's or helos from much further offshore;
(3) Who says lift fan F-35 only for close air support? Not Navy Dept.