Maybe bitcoin will die if no one sees it useful, in short, zero demand will end bitcoin, just like any other coins
Yup when the demand of Bitcoin will completely go in the market, and people stop to use bitcoins for anything. And the value drops to below $100 then that is the end time for Bitcoin. But this is not easy if this happens then all the other cryptocurrencies will lose their value in the market. People will never trust any cryptocurrencies.
The price of bitcoin is now largely dependent on investors who invested in it. Simple users have little impact on the price of bitcoins. Therefore, we can conclude that bitcoin will die when investors lose interest in it