[nickelpro]

And yet all of these systems basically work for day-to-day operations, and fail only under obscure error conditions.

It is totally acceptable for applications to say "I do not support X conditions". Swap out the file half way through a read? Sorry don't support that. Remove power to the storage devise in the middle of a sync operation? Sorry don't support that.

For vital applications, for example databases, this is a known problem and risks of the API are accounted for. Other applications don't have nearly that level of risk associated with them. My music tagging app doesn't need to be resistant to the SSD being struck by lightning.

It is perfectly acceptable to design APIs for 95% of use cases and leave extremely difficult leaks to be solved by the small number of practitioners that really need to solve those leaks.