Big smooth rolling front wheel where it matters.
Small easy to spin up back wheel where it matters.
To me that looks like the wrong way round.
Big smooth rolling back wheel, where the riders weight is, gaining more from the reduction in rolling resistance.
Small easy to turn and maneuver front wheel, where you need the handling.
Of course, I’m thinking hardtail. Rigid I’d be thinking full 29er. But what do I know, I can see the advantages, but haven’t tried one yet.