It simply isn't reasonable to ask people to take the risk that their money can disappear because of an unbacked-up file.
We don't ask anyone to take that risk.
This is the price of ultimately controlling your own money. Bitcoin makes it possible to store money in a single file; anyone who does not like this should not be using Bitcoin. If you are likely to forget a password, don't encrypt the file, but risk theft. If you don't want to back up a file, try your luck with the longevity of a hard drive. This entire thread is debating a security "threat" that is inherent in any system which gives you direct possession of anything.