When I saw this image, my first thought was what @Scott Kenny said:this shape and size and the fact that it's manned screams more than just gas hauler to me. Just a thought, what if we split the tanker role into 2 fleets. 1 converted commercial aircraft sitting far behind away from threats. 1 connector types that has large volume like this one that can act as tanker and a secondary offensive role that supplement NGAD. connector type can loiter behind NGAD and act as missile arsenal and can take additional gas from the more conventional type that sit even further back while pump gas for NGAD whenever needed in contested airspace.
This would justify its existence more than a pure stealthy tanker while being much cheaper than NGAD being stripped of all the exotic stealthily embedded sensors and kinetic performance.
With it's shape and wings, it will be way more than a tanker, if not commanding CCAs and getting a dozen of AIM-174B in it's rotary launcher