Are you looking for the real reason behind the massive declines we've seen recently?
The answer is 2 words = Interest Rate.
The US is going to keep on raising it and investors are looking for save haven that pays sure dividends ... so the US Dollar that everyone has buried in the last decade is outperforming all the Cryptos, and soon the EUR/USD will hit a parity (it's $1.25 now, it won't stay like this for a long time).
History always repeats itself, one way or another.
I disagree with you , not even close to the real problem , no relation between cryptocurrencies and fiat currencies and the decline of bitcoin and the other altcoins is caused specially by the FUD and the rumors of bitcoin regulations by governments and this is what created the panic what pushed people to pull off the money from the market and dropped the price because of this massive selling process , this is the real problem and nothing else dude .