I Dita looks so well isn't because of one particular item. It's a whole look. It's not just the porcelain skin or the red lipstick or the hair or the clothes though companies would want to convince you that buying a red lipstick would give you a Dita-esque look.
Dita looks like Dita because she is completely dedicated to a look. You don't see her wearing 80s jeans with 40s shoes. You don't see her wearing secretary blouses with nerd glasses. She knows very clearly what she wants to look like, the image she wants to portray and she ruthlessly sticks to that. No doubt, she has a great passion for period clothings but hers isn't an "effortless" look. Every piece of article on her is carefully calculated. The hair goes with the makeup goes with the skin goes with the clothes goes with the shoes goes with the bag goes with the jewellery etc. Right down to every curl of her eyelashes, every piece goes together periodically. She doesn't appear dated because she knows what shapes look good on her and she uses classically cut pieces. The piece might be this season, but it's also definitely something you would find 50s hollywood actresses wearing.
This kind of dressing (complete, calculated, after a certain look) is very consistent with the "50s housewife" kind of dressing. As in the mental process is the same. They love the clothes, sure, but they love more a put together look. She is literally dedicating herself completely to a certain aesthetic.
And unless you are willing to do that (adapt a complete wardrobe, style of personal grooming to what fits your body and features best), buying bits and pieces of her "look" and trying to wear it and give off her vibe is pretty hard. You'll end up like the hipster kids with rockability leanings.
