i think holdings of BTC are better because they are one of the fastest growing investment i have ever seen . investment of gold is safe but groes with a slower rate comparitively .
Holdings of both btc and gold are better if you have these two. But since it's hard to acquire gold assets and it's popular already. Investing or having holdings in bitcoin is still new in the ears of the investors so it is not yet that late if you want to have some decent holdings with it. You only need to be focused with this thing.
It is not at all hard to acquire gold assets. All you have to do is approach the friendly neighbourhood jeweller and buy a gold bar or coin from him. Buying bitcoins is hard, especially for people who are not Internet savvy.
In the market today the market of gold is that vast already. And we know that if an investment is crowded the difficulty gets higher and that's why I said that acquiring gold nowadays is that hard. I will always prefer to the new investments that has something to grow in the near future and has the chance to make bigger return.