What could such a limitation be? I'm 100% layman, but some have suggested that falcon wing doors could be an issue, since seats can't be anchored to c-pillar and that would cause that seats themself have to be stronger than normal seats. So folding mechanism would make seat too weak. But could this really be the case? Couldn't materials like titanium be strong enough? After all there are limitations what kind of g-forces human body can tolerate and if g-forces rip your internal organs before seat, the structure is strong enough. Of course exotic materials can be tough to master, but I can't imagine, that this issue would not be eventually solved.