I believe that many altcoins will die off due to week fundamentals, all the weak projects, meme coins and speculative tokens will vanish over time. Bitcoin is more entrenched than any other crypto that's why I believe that it's strength will make sure any crypto that actually survives, must justify its existence
I believe that in the near future, there is no coin that will kill Bitcoin and I also believe that Bitcoin is becoming a gold. Consider that Gold has been strong for decades and so will be Bitcoin because it's becoming a digital gold. Just look at what happens around it, big corporations like Black Rock forced SEC to approve Bitcoin Spot ETFs. Some US states also keep some of their reserves in Bitcoins, banks are also allowed to keep Bitcoin reserves. Bitcoin is in a direction where commercial banks, big corporations and governments (countries and states) will soon keep a good portion of their reserves in Bitcoin. This act is a guarantee of Bitcoin's success, which automatically means the kill of many altcoins.
Btw to be fair with you, Bitcoin is not the killer of other cryptocurrencies, they die because they do not solve real-life problems and do not have any reason to exist, that's why they die. Competitive altcoins like Ethereum and Monero have their spot in crypto space.