Not really a fan of that definition.
Everything is capital. Something that looks like it is for consumption might in the end give you new ideas or inspiration or broaden your horizon and hence be very "productive". On the other hand, something that looks like capital could totally be a net cost and on its way out...
...to find the things that are useful to invest in is hard and textbook definitions dont really help. More than that - the kind of future people want is very different depending on what groups of people you ask and hence what they value in life.
With so many countries and billions of people all we have is a lot of diversity and markets with sound money help a lot. Todays capital might be tomorrows liability.
Markets are a useful concept. "Capitalism" is more an ideology that was since the dawn of "capitalism"
History of capitalism - Wikipedia
...never really anything else than connected to a "money printer". The rich capitalists always had access to the printer and hence whatever bitcoin brings us is so different, that it is just purely confusing to cling on to wording that was for centuries connected to something that was vastly different then the near future brings.
But have fun clinging to this term - it's not really useful to say the least.
