I think the difference is that flight opened up quick trips where you might want a bag with just enough clothing for a few days. I also think the 1970s also hits a point where peoples' clothing had become a good bit simpler. Wheeled bags shine in airports for carry on bags.
"I think the difference is that flight opened up quick trips where you might want a bag with just enough clothing for a few days."
Traveling salespeople etc. would often go on relatively short trips, even in the steam engine era. We underestimate mobility of pre-WWII people by a lot...
The point about simpler clothing is really interesting. I can imagine that this could be the crucial difference.
Why wouldn’t quick trips work on surface transport? Sure, it takes a long time to go far - surely nearly nobody ever went from London to China and came back a week later until it was practical to do so on planes. But for short distances it still would have been practical. I’m guessing there were people going from London to Manchester for a few days well before the 1970s.
The railway companies in Britain built their own hotels. The first was in 1839:
> The first railway hotels in London were built at Euston. Two hotels designed by Hardwick opened in 1839 on either side of the Arch; the Victoria on the west had basic facilities while the Euston on the east was designed for first-class passengers
And in Manchester:
> The Grand Junction Railway, Britain's first trunk line, was completed between Curzon Street railway station in Birmingham and Warrington Bank Quay railway station, Warrington, on 4 July 1837. Through trains began to convey passengers from the station to Birmingham, and a separate booking office and waiting room were provided. From 17 September 1838 there were through carriages to London Euston by some trains after completion of the London and Birmingham Railway in that year. This increase in long-distance services resulted in one of the first private railway hotels opening in Liverpool Road.
I think you also need travel to be available for a class of people who are both expected to change clothes every day and did not have porters carrying their luggage.
