BTC is not only the first coin but it has symbolic value for the entire crypto market, one symbol of the blockchain revolution.
Just like gold, there are thousands of metals produced such as steel, aluminum, silver, etc., which are widely used in daily life. but gold has always been the most valuable metal, still number 1.
So there will be no altcoins that can replace BTC although ETH, Sol, Tron or Xrp... have utilities, applications and technologies that are far superior to BTC.
Actually you made the wrong comparison the reason why gold is expensive is simply because its rare and the extraction process cost also bit expensive but one day if asteroid mining became reality we can expect the supply of gold will increase which will greatly reduce the gold. Meanwhile bitcoin can be replaced as well but until now every other project created is trying to become the next bitcoin not better than the bitcoin.
I don't know what was the OP thinking that Bitcoin would be replaced by some altcoins who are just merely a copy of the original one. If you want to beat or replace Bitcoin then better make one that has utilities such as your altcoins pick and decentralized at the same time that cannot be controlled by no one.