Material wealth, before 1800, was usually a metal. It had legible value anywhere so you could use it to defend or attack the means of production: land. People say land was wealth before industry, but "owning" it just means having the means to defend it (which could, in modern times, be a legal claim; no one wants most land enough to take it by force) so what you really needed was the metal to fund an army. You were rich if you had gold and could defend the land you had and get more if needed.
Between 1800 and ~2075, wealth is debt from an establishment like a nation state or corporation. Being rich means that you can call in favors. You use this debt to build an industrial or business process that gives you a good return on investment. You don't need to own the gold; you just need a certificate saying you had the legal right to it or that someone owes it to you.
In 2025, wealth is going to be access to talent. I'm writing a monstrously large blog series and the penultimate post (21 of 22) is going to hint at the economics of that. I'm afraid to get too specific; that might compromise a startup idea that's been percolating in my mind for a few years and might be ripe in the mid-late 2010s. But we're now in a world (convexity) where capital is scarce in comparison to the talent that can do something with it. The new currency (post-2075, I'd guess, because people are conservative when it comes to money; metal and debt currencies aren't going out of business any time soon) will be some proof-of-work model related to technical talent but I've got no idea what it will look like.
How to define money in that world is an open question. That said, I don't think we need to get rid of fiat currencies just yet; I don't know what would replace them.
With BitCoin, there's no intrinsic value. Someone else could create a ZitCoin with similar structure but not that stupid enforced deflation designed to enrich the first entrants. Now it's a red-ocean with a zillion copycats, so we have ZitCoin and FitCoin (for gym memberships) and PitCoin (for dog breeders) and LitCoin (for getting drunk) and a couple of other *itCoins too crude to mention. Now it's just about branding; most of these alternative currencies (which are too volatile to be real currencies) fail.
There's this idea that BitCoin is going to become the next Black Lotus (a $1000 Magic card) but the vast majority of Magic cards have lost value (and all of the cards from the copycat TCGs that flooded the market in '90s). I remember when Shivan Dragons were $25 because a 5/5 flying creature for 6 mana was badass. Last I checked, they were about $2. The thing about a Black Lotus is that (a) it's extremely scarce and indivisible unlike BTC, and (b) there's actually something you can do with it, which is play a powerful Magic card legally.
Until you can get 3 mana of any color out of a BitCoin, or drop it from at least 12 inches and destroy permanents based on table position, I'm going to be skeptical.