In my opinion if there is no other digital currency besides bitcoin, there are 2 possibilities. Firstly because of the absence of altcoin or cryptocurrency other than bitcoin, the market demand in bitcoin will be even greater and prices will go up, this is if the user still believes in bitcoin. The second is because there is no concept development on the blockchain for bitcoin, users may not be interested anymore because I think there will be many problems that arise in the market, which will have a negative impact, so bitcoin is abandoned. We need altcoin to develop the technology available on the blockchain, because there are still some weaknesses in technology and can still be developed as well.