Plus, Gold might be highly volatile by some stock standards but it barely moved a percent over the last 24h while Bitcoin does percent movements on the hour mark.
Stores of value require a predictable purchasing power to be useful, bitcoin does not have predictable purchasing power. Or the guarantee that in 20 years I'll still be able to use bitcoin at all.
The major difference here is that gold has been used for about 2000 years plus now and has proven to be somewhat valuable in a functioning society. Bitcoin hasn't been around for a full percent of this time and nobody knows if it'll be around for another percent to begin with.
Ring me up though if Bitcoin will survive the next 100 years for sure.