This has been said by my boss twice in the last week or so.
We provide tea, coffee and squash for staff refreshments and we get through quite a lot of squash, especially in summer. On signing off the purchase boss said "who even drinks squash these days, it's so 1970s".
Then a colleague had arranged a small spread for a meeting including some Mr Kiplings cakes. Boss said " 'Sally' still thinks it's the 70s."
Apart from been quite sneery, are those things so obsolete? They obviously still sell if you look at supermarket shelves. I think what's actually happened is my boss has become middle class since the 70s, so these are things she remembers from her childhood, but wouldn't buy now, whereas families from her original background (as most of our colleagues are) are still happily using them.
I might tell her that if she says it again 😆