All calculations of this sort are fatally flawed because they assume all the coins in one address are owned by one person. That would be like calculating the US Gini coefficient assuming that all bank accounts are owned by the CEO of the bank.

> All calculations of this sort are fatally flawed because they assume all the coins in one address are owned by one person.

But don’t the calculations equally assume coins spread out across multiple addresses aren’t owned by one person, when in fact they often are?

Sure but that doesn't offset the first problem, it's just an additional problem. In fact I believe it could move the fake Gini coefficient in either direction depending on how each person splits their money.

If many coin owners share the same address, that is not very decentralized, is it?

that's like saying that the internet isn't decentralized because lots of people interact using facebook. that address isn't decentralized, much like facebook isn't. that doesn't mean that bitcoin or the internet aren't decentralized.

"Decentralized" means little without more context. The issuance of bitcoins isn't a legal monopoly. In this sense Bitcoin is "decentralized". On the other hand the Bitcoin blockchain is a centralized ledger, which is distributed, but nonetheless centralized. So which one is it? Centralized or decentralized? It doesn't matter because at this stage "decentralized" is being used as a mere buzzword rather than to convey a precise meaning.

> that's like saying that the internet isn't decentralized because lots of people interact using facebook

Yes, and I do say that. Decentralization is a lot less interesting if most people just end up centralizing anyway.

Who shares a bitcoin wallet or operates one like a bank? If anything the opposite is more likely, several bitcoin wallets belong to single individuals, probably in particular for some of the high net worth ones in an attempt to obfuscate ownership, which if anything, understates how concentrated it is.

> Who shares a bitcoin wallet or operates one like a bank?

Almost every bitcoin exchange.

It's typical to pool user funds into a relatively small number of addresses.

A system which is 12 years old, of which many people have not heard about, don't understand, or may not even care to understand. In some countries its illegal to use. Most countries have unfriendly tax treatment (capital gains on your coffee purchase). Can't be paid in it. Can't yet pay your federal taxes in it. Uncertain if the government will one day ban it.

> Most countries have unfriendly tax treatment (capital gains on your coffee purchase).

That's definitely unfriendly tax treatment. Is it different from the tax treatment that applies to national currencies?

Yes. It's the same tax treatment that applies to gold bullion or barrels of oil - volatile commodities that are at least partly speculative investments rather than stable mediums of exchange.

What is the tax treatment that applies to national currencies?

Country-specific, but often you don't have to account for them up to a certain limit, and/or you can treat anything you buy in a foreign national currency as having been bought at what you originally paid for that currency.

Not sure in the US, but in Canada you don't need to report capital gain on foreign currencies if its under $200.