In the last article the quote said that Disc Brakes became Standard first in the rear wheels of cars and trucks but this isn't true

 Instead what it should have said is that disc Brakes became standard in the two front wheels of cars and trucks by the 1990s. 

The reason for this is that a majority of your braking power is in your front steering wheels because of what weight does in cars. So, putting your disc brakes in front is far more useful than putting them just in the back because most of your useful braking power is in your front two brakes.

And Rear Brakes are more for emergencies anyway for when your front brakes go out from a broken brake line or something like this and your emergency brake is usually tied to one of your rear brakes too.