I think all of you guys are on the right track - it is all that, and more. On the company level, marketing is about crowd appeal; selling as much of an item to as many buyers as possible. I learned early in life that "fashion" and being "cool" is, essentially, a copy cat endeavor, with the crowd trying to look and act like what is generally considered cool - essentially a matter of mass appeal. Nostalgia sells because it links a current new product to a older, already successful and popular product, giving it crowd appeal - even if the connection is nominal, or in name only.
But then, we also know real artists wander about in different directions, and do not follow the crowd - while some become trend setters, they are still cutting their own trail - they are leading and not following the crowd. Marketing is aimed at crowd appeal - so it makes sense to link one's current product to a successful past, almost as if old stuff is always better than the new stuff. People want the good stuff - the cool stuff - so it pays to link one's line with tradition. But, it is just copy catting to make buyers feel they are getting the good stuff. After all, everything was made better 1) by hand, 2) in the old days. (Lots of stuff is sold as hand made - when it is not! because it sells better that way. The worst fraud is Tito's Handmade Vodka - because if you know anything about distilling spirits, you know it cannot be made by hand! But, try telllng that to young people looking for the "best" way to get drunk!)
Gratuitous Sidebar - I decry the proliferation of YouTube videos and Internet articles purporting to list the "10 best whatever", such as Ten Best Microphones for Boring Podcasts, or the Ten Best Headphones for Hopeless Bass Heads, and etc. Neat idea, but most are simply lists of already popular products, with links to Amazon and elsewhere to earn a commission for driving sales under an affiliate commission program. Unfortunately, they are most often fake reviews, written by people who have never tried, let alone own, all of the gear they review.
In the end, it is all about crowd appeal - getting the most folks to buy what is trending, and nostalgia sells new stuff which is conceptually linked to successful old stuff, with a tradition of success. Folks waht what other folks have - fashion is just copy catting to have and be cool - like everyone else. Nostalgia links now the past, I guess.
Disclaimer - a spontaneous untamed group of wild thoughts spawned by previous comments from more articulate souls. James