Bitcoin can never be responsible for the decline of all those coins that are dead and not in good condition because Bitcoin is a very valuable coin, this coin cannot beat any coin, but because there are no trader and investors, all those meme coins, shitcoins, die. And all these coins can never be valuable.
Bitcoin is BTC. Bitcoin has nothing to do with anything else, let alone being responsible for other coins. If others want to emulate Bitcoin, no one is stopping them, but their efforts to emulate Bitcoin have not been successful to date.
Bitcoin has never aimed to be a competitor, but if others want to compete with Bitcoin, they are welcome to do so.
Individuals, investors, or traders have the right to choose between Bitcoin or other coins.
If you want safety, success, and long-term profits, Bitcoin is the choice. If you want high risk, the choice might be other coins besides Bitcoin.