"many people believe that crypto currency is a bubble"
Simply saying "Cryptocurrency is a bubble" is stupid. However, denying that the majority of the Cryptocurrencies is in a bubble is just as stupid.
As much as I admire Blockchain technology and its result, Cryptocurrencies, it's a fact that approximately 97% of the Cryptocurrencies currently in existence serve no real purpose, are outdated/beaten by other cryptocurrencies or will certainly be.
The price of Cryptocurrencies should be related to its use, which makes sense, ay?
Well, the current price of the majority of the cryptocurrencies isn't related to their use at all. There are multiple Cryptocurrencies faster, cheaper, more anonymous, more secure & with cooler names than "Bitcoin".
Yet, Bitcoin got the lead with a market cap of about 150 billion dollars at this time. Why? Speculation!
Speculation is what drives the current crypto-market and, sadly, this results in outdated Cryptos like Bitcoin rising up. Just as well as most of the other top-coins.
Speculation is what causes the majority of the Cryptocurrencies to be in a bubble.
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Given the low level of intelligence most people seem to possess, I don't think it's a great idea to have the whole world be involved in these Cryptos. If you just notice how so many people fell for the Bitconnect scam, then how can we expect the rest of the world to be able to even comprehend the purpose of Cryptocurrencies? We can't. Until they've become so user-friendly that centralized institutions can control Cryptocurrencies of people again, it won't be used by everyone world-wide. Period.