Does it mean "will be lost fast"?
This link doesn't help, I think.
"To any ordinary person, $3 trillion sounds like an awful lot of money. But if a bubble bursts in an economy the size of China's, the money goes fast. More to the point, China would have little incentive to defend the Yuan in the case of a burst bubble. The easiest way to deflate the (real) value of assets in China would be to just let the currency take the cut."
I'm no Economy expert but I think that when we are talking about a bubble burst, we are talking about the lost of value. Money is not lost or spend, it doesn't dissapear, money lost its value because prizes increase at a quick [fast] rate. You may have the same amount of money but you can buy less things because you can not afford some prizes.
So, I partially agree with @Jason Bassford
goes fast = the money will quickly disappear (be spent)
but this context is a bit more complex.
According to Oxford Dictionary
Used to refer to a significant, usually rapid, increase in asset prices that is soon followed by a collapse in prices and typically arises from speculation or enthusiasm rather than intrinsic increases in value.
From Cambridge Dictionary
to say or do something that shows someone that their beliefs are false, or that what they want to happen will not happen
