It is extremely telling that the IMF fears bitcoin as much as it does.  Some may be stupid, but many there know that bitcoin is significantly better money than fiat.  For example the USD has lost around 98% of its purchasing power under Fed (mis)management.  That is one reason why a US $20 one oz gold double eagle now costs around $3300-$3400. (It may be much more if you include any numismatic value of course.)  The IMF knows that there are plenty of smart people around the world who want to protect themselves from authoritarians of any stripe whether socialists, communists, fascists, totalitarians etc. and can use bitcoin to do so.  Of course they can use gold, but it is not nearly as portable etc.

Anyway, I believe it is indicative of the fear that they have of a non-government controlled money since for around 112 years now the US has been at the mercy of people who want to tax them via inflation and control them via controlling their money.