I agree with your opinion that bitcoin will not last forever, but for now bitcoin remains my choice. bitcoin will survive even if not forever. because there is nothing eternal in this world. there is a beginning, there must be an end, maybe in the future bitcoin will be replaced with better technology from blockchain.
There is bound to be a new technology that is better and superior to Bitcoins in any way eve though it is currently the leading cryptocurrency in the world. Faster transactions and lower fees will contribute to that.