I never understood anything about it
There's two distinct things. There is the original technology, which is interesting and may have some utility. Completely theoretical.
Then there's the scammy, speculative, money laundering nonsense that it is in its current form.
There’s also a big difference between crypto currencies and crypto currency exchanges. Crypto currencies are mostly worthless as their utility is still pretty limited and there’s still no good way for them to have high utility for the average person right now. But there’s potential there and as long as the currency doesn’t go away, there’s still some potential value.
Exchanges allow folks to buy and sell crypto currencies or even fractional shares, but like the stock market, you don’t ever hold the actual currency. The obvious danger in that is that the exchanges have zero regulation and these big exchanges keep stealing everyone’s money and folding (see Mt Gox).
If this whole thing isn't Toto pulling back the curtain, I don't know what will be.
Take a bitcoin. It is a currency which is, in the simplest terms, a medium used to exchange value. Thing is, you can barely use it to exchange value. It's not like you can walk into your local 7/11 and buy a pack of gum with it. First of all, we already have plenty of currencies with much higher utility. They're all backed by nations and work within each nation. Some, like the US dollar, can even be used quite easily in many foreign countries as an exchange of value. So, you have bitcoin and other crypto, which has just a fraction of a percent of the utility as existing currencies, why would anyone use it? They don't. Yes, it has a way of tracking everyone who ever owned it (sorta), but really, when I want a pack of gum, do I care that the Sultan of Brunei once owned this dollar 7 years ago, or do I care that it buys me a pack of gum? On top of this, the lack of regulation has created a situation where the entire crypto space is absolutely flooded with scams, from ponzi schemes, to rug pulls, and to outright theft/hacks. Additionally, many cryptocurrencies (including Bitcoin) burn up tons of energy to "mine". Like, using more energy than most nations. Humans are literally burning coal to run machines doing cryptologic calculations to find the next bitcoin. Why put up with all of that for a low utility store of value? And beyond that, why put up with all of that AND decide that it's worth somewhere between 20,000 and 50,000 times the value of a dollar? The dollar is much more useful to the user, and it's not even close. The real true value of a bitcoin is probably a fraction of a penny. Everything else built into its price is nothing but speculation and irrational exuberance.
It's nonsense. I can't remember the exact quote but I agree with Warren Buffet who said something like, "If someone offered me all of the cryptocurrency in the world for $20, I'd turn them down."