I agree with this to an extent. Where I'd diverge is on the question of whether we should say that some of the reasons things aren't "as good" as they were in the post war period is because certain segments of society (business interests, capital owners, etc) have used their influence to improve their prosperity at the expense of the average citizen. To the degree to which that's the case, describing the post war period as "lucky" will gloss over the systematic process of favoring corporate interests over individual interests and normalize the idea that a strong prosperous middle class is an abnormal scenario that we shouldn't attempt to replicate. I don't believe it's easy to return to the specific economic circumstances of the post war period but I'm not sure we're trying very hard right now in the U.S.