The lesson not learned, as with all so-called ‘people’s revolutions’, is the end result of certain collapse, followed by excuses and ending in reassurances that the idea itself is sound. Marx also agreed that the state would eventually wither away under communism, it never did and never has.
Ideologies are judged by results, not beliefs and just as communism provided heaps of corpses as proof and Christianity the inquisitions, witch hunts and crusades, so too the anarchists believed that they could create a stateless and classless society and failed miserably. Anarchism is only one of the many ideologies arising from the late 18th to the mid 20th century in response to a changing world, which saw the end of European absolute monarchies, serfdom and ideas of how society ought to proceed.
That is not to say anarchism faded out entirely. It is still alive and well in some parts of the western world, but at a micro level of small ‘hippy’ like communities, reminiscent of the 60s, whose ideas could never function above that level. This is often cited as proof that anarchism