The real reason to hold Gold and Bitcoin is human tendency to secure future or to fulfill security needs compromising present.
Due to sky-rocketing inflation, mere savings won't gonna help developing capital for person. Certain contingencies like accident, etc can shake the entire budget of individual. Hence, to stabilize one's financial position and to give catalyst impact to savings, person goes for investment in gold and bitcoin.
This is true, and most mainstream economists won't say that saving is a good thing socially too, under the right system.
It's only under today's system of theft and deception that saving becomes a 'problem' for the economy (called the 'paradox of thrift' by certain economists.)