The reason why Bitcoin is called digital gold is that people are very curious about Bitcoin nowadays. Just like gold, even though its price fluctuates, it has a stability, gold has maintained its stability for a long time. Bitcoin is also a means of maintaining value for many people nowadays. If you look closely, you can understand that the most interesting thing is that its number is limited, just like the gold reserves in the world are limited. That is why many people call it digital gold.