Indeed, and I also think its a primary currency, think about the fact when everything will collapse the gold will still be standing and we will pay with it for sure if every currency will collapse I'm pretty sure about that.
Gold is just the most important currency in the world in my opinion, I think if the bitcoin fails the gold is the best currency to invest in in my eyes, there is just so much profit you can make with gold on a long term.
Gold is good for being used as spare currency for when fiat money isn't worth anything anymore and digital currencies have no way of surviving without internet. So, if something happens, then we can all fall back on Gold.
Gold holds more number of trusted users in compare to bitcoin, but the scenario will change in coming years when bitcoin will get more popular and powerful.
Right now as gold has got more acceptance which makes it better than bitcoin, but with the potential bitcoin has it would soon exist as an alternate currency and becomes better than gold.
I can say yes gold is better for bitcoin because golds price rises as years past and it cannot die because it is a precious mineral mine from our sorroundings to years past the price rise and surely it will be the most expensive thing will be exist aside from diamond. But bitcoin is floating money in world wide web And we never know what will happen to it in future although it is strong today because it has gained many users but how about in future we cant tell.