Because a lot of money was withdrawn from cryptocurrency, this was the cause of such a drop in Bitcoin and all other altcoins!
it could be the reason why the crypto currency has decreased and there are many more reasons for the crypto currency to decline and one of the bad news can make a decline and all the development of the crypto currency depends on the investor itself
Well it's cleansing itself as well. I don't think we're supposed to hit 20k in 2017 in the first place. Hype did a lot to draw people in especially those who didn't even know what they're doing. The bear market purged crypto of those ignorant people thinking about quick money. It may take a little more time still, but i think we're ready to move forward slowly now.
You has a point in your opinion since a 2017 bullrun is not expected to make a drastically run now we see a long run bearish trend to clean all the mess and those peoples who have a strong hand & high believe will be stay in crypto also those project that useless will be dead.
Hoping this coming 2020 halving will be a way to stop this down trend.