Which is the same accusation we can make against gold bullion then which are in my experience not fungible with each other and different dealers have different things they are willing to buy and sell to you.

Bitcoin isn't money at all, it's a currency.  Fungibility is one of the requirements of money.  Money can't just randomly morph from one thing to another with forks or alterations.

Money = has objective, static traits

Currency = random arbitrary bullshit some guy makes up and constantly fiddles with aka bitcoin

This is why it's called "cryptocurrency".  Currencies are not a store of value either.  People just make believe bitcoin is whenever they get on the profitable side of a pump and dump.