In my opinion, a currency lasts longer and does not fade away as long as the demand for the currency is high. With the passage of time, other coins having good projects on their back will also surface but they might not be able to outshine Bitcoin because it has already captured a big portion of the market around the world and even ETH, which is thought to have advanced technology than Bitcoin, has not yet reached that level, I do not think any other currency will in future. With the passage of time, we would be having technological advancement in Bitcoin as well.