A pyramid scheme involves selling a product - something like knives or energy drink. But the actual thing which is sold are licenses to sell the product. Each licensee passes some of their profits up to their licensor who is the licensee of someone else and passes along part of that and so on. Eventually the last round of licensees are stuck with product that they can't sell and the upstream licensors are getting rich from the "pyramid" of downstream licensor/licensees recruited into the scheme.
Well, there are no Bitcoin licenses - anyone can mine it, hoarde it, spend it, etc. So it is not a pyramid scheme (or multi-level marketing scheme). The value of Bitcoin will not collapse if everyone in the world is using it.
A ponzi scheme is quite different. You pretend to invest an initial investor's money. The returns to that investor are paid out of money coming in from later investors. There is no opaque "fund" making "investments" when it comes to Bitcoin.
So what makes something a currency? It is:
* Medium of exchange - 100s of 1000s of merchants accept Bitcoin for payment
* A store of value - Bitcoin has had a nonzero value for 5-10 years now so it can be reliably used for savings
* Unit of account - This is where things get fuzzy. Things tend to be denominated in US dollars or Euros with Bitcoin converted at the spot price when a transaction occurs. There is no reason why Bitcoin can't be used as a unit of account, but it still has a ways to go before it is popular enough that it is actually used that way.
The Washington Post article places a lot of emphasis on the greater fool aspect of buying/selling/hoarding Bitcoin. This applies to all investments, and especially to stocks. Are you going to claim that the stock market is also a Ponzi scheme or a pyramid scheme?
Of course there's completely no reason to feel bad, it's a risky bet and one could just as well think about what fantastic sports bets he could have done in the past years.
Plus, without thorough technical understanding, quite a lot of trust is involved in believing that it can actually work.
2) "It won't be possible for the government to enforce taxes or seize assets" is not a selling point outside the criminal, libertarian, and anarchist communities. Most people seem to feel that the rule of law is too weak in the financial realm, not too strong. HSBC's money laundering for the cartels, for example, is generally considered a bad thing. Billionaires minimizing their taxes through tricky schemes are seen as villainous, not smart, by a simple (though not electoral) majority in the US.
3) Inflation is not a problem Americans have or have had since, like, the Carter administration. Given how leveraged most households are, we'd probably like some more of it. "Inherently deflationary" and "no central bank" are not compelling arguments, and just further the anarchist/libertarian branding.
Harsh yes but sometime you just have to call it the way you see it.
I'm not sure what you mean by ordinary people lose a lot of money with it but ordinary people have surly lost more money in the stock market than they have in Bitcoin. Saying Bitcoin is inherently fraudulent is simply false.
On the topic of computer security. If you are serious about your Bitcoin's security there have been secure hardware wallets available for several years now that are easy to use and eliminate the chance of theft from hacking. They have come down in price to the point where they are very affordable.
The Ledger Nano S for example is $50. It's also super easy to use and never exposes your private key to your computer so it can't be stolen even if your computer is infested with Bitcoin stealing malware. Trezor and Keepkey are similar devices.
