Bitcoin is an alternative choice if the other safe haven assets is difficult to get, there are a list of safe haven assets that might be a better choice i.e gold, yen or franc swiss.
Bitcoin volatile price become a frightening specter for investors who have just been involved in cryptocurrency investments, but the value is impossible to become a zero because it's fundamental supply and demands.
Hence it's a safe haven for anything at all. You place your money in bitcoin and you put it in more risk that keeping it in fiat especially if you don't have any clear idea about what you're getting yourself into. If you're thinking about the current financial system failing and that bitcoin is where you can convert to, you also would need to consider the risks of such venture. It's more likely that your money's value will fall before what you're expecting in the financial market happens.