bitcoin is maintained by core developers, would Bitcoin die a natural death if the developers no longer exist? Or if they stop maintaining/developing/upgrading the system?
As far as I know no one is developing bitcoin anymore, it was already developed way back in 2009. The one who maintains it is the blockchain, and blockchain is not maintained by anyone it is shared on the network and is being updated on every transaction.
Unlike Altcoins which have a specific purpose for its price to increase, the business where it is being used should be maintained.