gold can be manipulated easily because the same bar of gold is sold over and over.
a lot of people are (believe it or not) stupid enough to buy gold and leave it in a vault, only getting a paper claim on that gold.
Since the gold is often sitting for years or decades in the same vault, they can just resell the same gold and no-one is any wiser.
However, reselling the same bitcoin is pretty much impossible, as it's widely known rule #1 of bitcoin, if you don't own the private key you don't own the bitcoin.
Yep this is the reason the federal reserve doesn't allow countries to see their gold.
It's been sold again basically making the Federal Reserve a Bernie Madoff like ponzi scheme.
P.S. If the US Government disagrees i'd like a tour of the vaults. And will retract this statement