I have an incomplete idea
This is completely unrelated to technical side of Bitcoin, but i digress:
Man still needs to undergo a complete spiritual rebirth in his attitude towards his work, freed from the direct pressure of his social environment, though linked to it by his new habits. That will be communism. - Che
Built in tax or demurrage has not proved popular (see Freicoin). Socioeconomics 101 - people will not submit to a system which does not satisfy their needs. Current society is all about status and class. You need to first remove status and class by convincing people there is no need for status and class (good luck trying to override our ape instincts).
Then capitalism will disappear on its own.