I'll believe that this usage arose in the 90s, but how do you know this particular factoid? Is it because you were there at the time, or did it somehow come up while researching something?

A few years back I was watching a modern parody of one of those Rankin/Bass stop-motion productions from the 1970s, and the narrator used the phrase "that could be an issue", which sounded clangingly out of place to me, but I couldn't put my finger on why. I looked into it, and sure enough: there's no attested usage of "issue" to mean "problem" prior to the late 1970s, and it didn't become well established in casual speech until a couple of decades later.

(To be 100% fair, you could get away with a character using the word that way in casual speech in media set in the 1980s, but in context it would be incongruously formal. Before that? No dice.)

@trippingpossum replied:

This is fascinating. However, I do have a specific memory from the 80s, some one using “do you want a magazine rack? For all your issues?” In response to some one venting. Maybe it was just more common around here.

Funnily enough, that’s apparently the transitional form. The word’s evolution throughout the late 20th Century is roughly “a matter to discuss (in business or law)” > “a matter to discuss (with one’s therapist)” > “a mental or emotional problem” > “a problem”.

I'll believe that this usage arose in the 90s, but how do you know this particular factoid? Is it because you were there at the time, or did it somehow come up while researching something?

A few years back I was watching a modern parody of one of those Rankin/Bass stop-motion productions from the 1970s, and the narrator used the phrase “that could be an issue”, which sounded clangingly out of place to me, but I couldn’t put my finger on why. I looked into it, and sure enough: there’s no attested usage of “issue” to mean “problem” prior to the late 1970s, and it didn’t become well established in casual speech until a couple of decades later.

(To be 100% fair, you could get away with a character using the word that way in casual speech in media set in the 1980s, but in context it would be incongruously formal. Before that? No dice.)

#yeah and there are no historically accurate black people there (via @heavenly-havoc)

The knight is Black, which is the sole reason that people started questioning its historical accuracy in the first place.