In most things I do on my computer, a few seconds or a couple minutes of data loss is acceptable, but data corruption is not acceptable. Without ordering guarantees data can become corrupt, something from weeks ago can disappear because you tried to update it. that is what is unacceptable.

Perhaps compare to the uberblocks on zfs. You can wipe out the most recent one, or the most recent fifty, and still have a consistent, slightly rewound, filesystem. Take that level of consistency and add a notification when everything is written out, and you have a nice nonblocking fsync.