Passports and borders are not the only restriction to travel, though. I would wager that the distance traveled now-a-days for the average person is higher than in most if not all of history.
Just heard something on the radio saying mass tourism in my country started only during the 1930s. Almost a century later, (before the virus) the blue-collar working class was taking at least a week or two of their vacations in places such as Bali or the Maldives. So you're probably right: Zweig was probably speaking from an upper middle-class perspective, not far removed from the roughly 2% of the then-upper class.
