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.
I looked through most answers in the topic, most say about technologies and decentralization. But some altcoins have all that and more right now. And yes, as for now bitcoins reputation is the main reason why no other coin can replace it now when we can still talk about replacement. Next (I guess in many many years) the situation will change and there will be many strong cryptocurrencies and none and never as important as bitcoin now and that's why none of them would replace bitcoin anyway.