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I would say ram-air inflation of parafoil wings is very different – it's dynamic, not static like a bladder pre-inflated with a pump.

This Inflatoplane is more of a precursor to modern "tensairity" designs (e.g. some of Prospective Concepts designs). While certainly interesting, pressurized bladders in aircraft have so far been a dead end due to practical limitations (catastrophic modes of failure, wear, altitude pressure differences IIRC). The only flying wings where inflatable bladders are successfully used are kitesurfing kites. But those don't normally carry people up high.

Parafoil based designs on the other hand are now everywhere. Paragliders, parachutes, parafoil kitesurfing kites, even parafoil sails (SkySails).