At least when making a post, you should outline your points first even before going ahead to put your reference link. Not everyone has the energy to go over your link reading all that.
From the article, the four fundamental reason were;
1: lack of regulation
2: magic of supply and demand
3: a technology still in evolution
4: world conflict
I think points number 1 and 4 are the ones that have the most impact so that bitcoin becomes very volatile, there is no regulation on prices so people who have power can make the price go up or even down with the money they have as well as world conflict because of the conditions erratic will create a lot of good and bad news that will affect so that it has a huge impact on the price of BTC and becomes very volatile, but that's what most people like because the volatility of BTC makes a lot of people profit, especially speculators