Michael Plant wrote in
:

....
Curiously, once upon a time, Darjeelings were produced much darker
than they are now, or so they say. The greener style is a rather
modern development since so many people in North America and Europe
want them that way. I'd say they are more analogous to Oolongs since
they are subjected to a certain amount of oxidation. But, they are so
distinct that they deserve a category of their own. That's my opinion.
I'm told that 10 times more "Darjeeling" is sold than produced. Most
likely true. The customer will always be supplied.
...
Michael

If memory serves, the Darjeelings sold in NYC's Little India were more
definitely black teas in 1979, when I first was taught to make masala
chai. Of course, what you say about the 90% ratio of false D.'s was
probably true then too (perhaps with a lower percentage because there
was less of a demand in the Eurocentric market back then?), so I don't
absolutely know if the stuff I bought as "Lopchu Estate" off the shelves
in the Pleistocene was real to begin with...

Ozzy