For 2020 Campagnolo published this set of interviews with a rather pleasant selection of participants in the 2019 l'Eroica. I particularly like Mara Mosole's idea that one of the desirable qualities of cycling is that "it isolates you, because it's just you and the bike". Isolation is not fashionable - but in, my estimation, is grossly underrated.
These videos include some attractive shots of various historical Campagnolo derailleurs.
Browse associated derailleurs.
Campagnolo Corsa 1946