Yes, Bitcoin challenge the Mises Regression Theorem from 1912. Deal with it.
Bitcoin is money without intrinsic value: pure exchange information, no physical hassle nor some residual utility.
I disagree.
Bitcoins are perfectly comparable to gold. If you go back far enough with gold you'll discover it's most common use was basically as a collectible in the form of jewellery. And because this was true in an entire community that community figured out it can use it as a medium of exchange.
Well same thing goes for bitcoins. That guy who accepted 10.000 BTC for a pizza didn't necessarily accept the bitcoins because he thought he could give them to someone else at a later time and get a similar value for them, no! he most likely thought they were cool or whatever and wanted to hold some and decided a pizza for 10.000 BTC was a fair barter price.
And since an entire community of people felt that bitcoins are cool and wanted to hold some willing to trade something of value for them(it doesn't matter that this is just an online community), people slowly saw that they can use it as a medium of exchange. And just as with gold, we went from a collectible to readily accepted money within a growing community of people.
And before you say "Well but you see, gold was started to be used as a medium of exchange because there was always the fallback demand by the jewelers present.." I would like to remind you that there is no reason why at that time, when people had no clue about chemistry and all the other elements that existed, those people should have thought that this demand will persist until the end of time. People could have discovered something else to use for jewellery or people could have changed their mind about valuing jewellery. Reasonably those people only saw a demand, not a lasting demand. And this lets call it temporary but very evident demand was good enough to spark the transition from a collectible to money. Well the same happened with bitcoins. There was a short term demand for what ever reason that sparked the transition from a collectible to money within a community.
The only way this process can now get reversed in either case of gold or bitcoins is if either lose their properties which (besides them having a temporary demand as support) made them ideal to be used as a medium of exchange in the first place.