Many a time, we find ourselves in a situation where old ideas which have been proven false often still get some love. Perhaps, the most prominent of examples is astrology. This Economist article has given me a precise term for such a situation.
Quoting from the article,
... what Moisés Naím, a Venezuelan journalist, calls ideological necrophilia - a love of ideas that have been tried and proved not to work.
To a great extent, this nostalgia for (potentially stupid) ideas of the past was also symbolized as Member Berries from South Park.