My first visit to Guangzhou (which was called "Canton" back then) was in '80 or '81 (can't recall exactly).One of the things that struck me back then was that during "rush hour" the wide bulevard we saw featured a number of buses,a few army trucks,a few Soviet style limos and about 500,000 bicycles.With God as my judge!
My most recent visit was a couple of years ago.Bumper to bumper Toyotas,Kias and....Buicks! I saw more Buicks there in one day than I see in a month here!
Although it didn't occur to me at the time you may very well be correct to say that the people in the fields are older folks...I didn't pay close enough attention to notice age.
It’s mind-blowing how China transformed so quickly.