Large gold miners as a sector underperform Gold due to consistently rising costs over time. Margins compress after Gold price peaks as the Gold price drops but production costs continue to increase.
Also, until the 1990s there were broad opportunities to hedge against inflation. Until then gold stocks did not face any competition. Now you can buy metal ETFs and emerging market funds.
Gold miners do outperform coming out of significant bottoms as well as during major Gold price breakouts. Should Gold rise from $1800 to $4000 in the next 3 years, gold stocks will outperform Gold massively from $1800 to $2700 but not much after that as input costs will accelerate.