I guess its not so much offensive as "dear god, this was NORMAL at one time." Then, I feel a mixture of disgust and contempt for people who idolize the 50s because they watched a few episodes of Leave it to Beaver.
Actually, that kinda goes for people who glorify the past in general. Now, there were good things about the 50s, just like there were about the 20s, 60s, and 80s. Those, are at least a -little- more understandable than people who are actually under the mistaken belief that what you see at a typical Ren Faire is what you'd see in the Renaissance.
Its odd how quickly people forget the Black Death was even a thing, much less that it wiped out a giant chunk of Europe. Guess I remember because one of my occasional recurring nightmares is that I, somehow, contract the plague, manage to survive, but am pretty much outcast by everyone because of the horrifying scars it left me with.