Here in the US we don't have any viable choice but to travel by air for long distances. I think it'll pick up here sooner and faster. Our passenger rail infrastructure has been purposely neglected to the point of near obsolescence and people aren't interested in a three or four-day drive. How and which US airlines will survive is an interesting thought exercise since regionals tend to be more on the edge, and keeping service on the non-major routes may require regionals to be completely absorbed into the surviving majors. The aircraft are already configured so we'd have to accept the pitch and density inside, though for the interim middle seats could be kept empty, etc.