Fool people? as in, “this was made 20 years ago, but no one knew about it until a couple of weeks ago, and BTW, if you run into one of the actors in public, they all just have Dick Clark syndrome, that’s why they look the same age as they did in the series”?
I don’t know. The problem with retro shows is usually that the point is the retro-- Happy Days was about the 1950s, so it’s more 50s than Leave It to Beaver, in that, for example, it mentions lots of people by name, such as the time when Richie wanted to work for some political campaign that was the party his parents didn’t support (I don’t remember who). I don’t remember a single politician’s name ever being mentioned on LITB. Happy Days did episodes about things like people not going to a party at someone’s house because a black person would be there. There was never a LITB episode like that. The LITB producers couldn’t count on a particular audience reaction or sympathy, whereas by the 1970s, the producers of HD could count on the audience wanting the party to be integrated.
Also, retro shows tend to exaggerate the fashions, partly for comic effect, and partly because they want to constantly keep the era in the fore. That 70s Show had some wild fashions (I was never a regular viewer, though, so, no examples). Compare it to One Day at a Time. The clothing barely registers as dated. Valerie Bertinelli has a Farrah Fawcett do for a couple of seasons, but beyond that, the show is not nearly as marked as you’d expect one with two high schoolers to be. The Partridge Family has a more dated look in regard to the fashions (it’s also a little older than ODAAT), but it was about people who would have worn exaggerated fashions, and even it is not as marked as the fashions on throwback shows.
Then, there are topics that would cause audiences today to roll their eyes, but that you’d have to cover if you wanted the conceit that your series really was made in another decade. For example, virtually every show in the 1970s had a “bad computer” episode. Usually, it had a computer overbill a person for something, but there’re some variations. Invariably, someone who works with the computer insists that “the computer can’t make a mistake.” No one ever bothers to mention that a computer is only as good at the data entry tech. The TV show character bangs their head against the wall again and again, and the message is clear that computers are nothing but a headache.
If you did an 80s show, you’d have to stick in a few very special episodes covering topics that were big deals at the time, like someone unmarried having a child, or someone having a classmate with HIV. You’d also have to have at least one molestation or date rape (depending on the age of the cast and the demographic), and one “don’t do drugs” episode. When you CGI in your 80s celebrity to tell people not to do drugs, it better look good. Bonus points if you can pick someone who was super famous then, but either no one has heard of now, or has done something disgraceful in the interim, such as Dan Quayle (yes, I realize most of his VP term was in the 90s, but he was a senator before that), or OJ Simpson. Those people would be embarrassing to have on a show now, and no one would choose them on purpose now for other than verisimilitude.
What would be the point? This is the kind of thing people do for a grad project in film school. It’s like Gus van Sant’s Psycho remake: more of a curiosity than genuine entertainment.