When people say things like that what they usually mean is the volume of bets on the price of gold in the futures markets is much larger than the trading in either physical gold or ETFs representing physical gold.
Which doesn't mean ETFs like GLD are not real. It just means that if I say I'll bet you the price goes up, we settle the bet at $100 for each dollar the price moves, that is independent of us actually owning any gold.
Which doesn't mean ETFs like GLD are not real. It just means that if I say I'll bet you the price goes up, we settle the bet at $100 for each dollar the price moves, that is independent of us actually owning any gold.