I will prefer to diversify my investments and will choose both of them as both are good investments for the long term and if bitcoin fails in future then also I can expect some profits from gold as gold will always give good returns in long term.
I don't think it's guaranteed that gold will give good returns in the long term. You will not lose a big part of your investment with gold that's for sure, but imo the value of gold is a bit overestimated nowadays. Yes, it will never drop to zero, but it could drop 20% or even more in the future.