What are the fates of the various generations?

From the text:

And men will not understand us--for the generation that grew up before us, though it has passed these years with us already had a home and a calling; now it will return to its old occupations, and the war will be forgotten--and the generation that has grown up after us will be strange to us and push us aside. We will be superfluous even to ourselves, we will grow older, a few will adapt themselves, some others will merely submit, and most will be bewildered;--the years will pass by and in the end we shall fall into ruin.

The generation that came before them will move on with their lives and resume their occupations..... things will go back to normal. The generation that comes after will merely push them aside, having no wish to live in the past or dwell on something they'd never experienced.