[martinald]

Ryanair takes about 30 minutes to turn a plane around with say 170 seats. It's also a large object that requires spacing to get in and out of the gate.

There's no real way I can see to improve airport design with those constraints.

You can fit maybe 4 platforms each holding 10 car trains in the space of one gate at a train station.

A380s require even more space and take even longer to deplane and board, so I don't think fewer but larger planes would work either.

EG: Atlanta airport does around 100m pax. So does Waterloo station in London. Look at the land take and size of terminals required in each of those cases.