They have already moved it to the 90s with the new overlapping generation teaching. My guess is they will soon be referring to a single generation that started in the 90s.
I was wondering why they used such a confusing explanation to extend the "last generation". And I think I figured it out.
The explanation is much more confusing than it needs to be. I believe this is on purpose. They know that most people will be embarrassed that they are too dumb to get it so will just go along.
That means when they go about dropping 1914 all together and just concentrating on the 90s all the confused people will be relieved that they have an explanation they can finally explain.