You're talking like this happens all the time though, or specifically the airline loses your ticket record. I can't even think of a bank error that would somehow be involved in a way that this helps you really - banks have every incentive to be as close as humanly possible to perfect in their record keeping, because when they aren't, they get sued, they get slapped with fines from the government, and they lose customers. The entire sales pitch of a bank is trust.

But what really seems to be happening here is you're suggesting that someone has both lost their ticket, and the airline at the same time lost their record of the ticket. This is exactly the same as

Multiple parties lose their records at the same time. Possible but unlikely.

You can stand there with your NFT all you want, the airline can still say - we don't recognize it as valid due to a screwup in their system, same as they do with a CC receipt or a printed ticket I guess. They can and do bump people from flights they agree have valid tickets all the time. And now you're back to what? Complaining to customer service or suing them (cause you can't force a bank to get back your crypto from the airline like you can dispute a CC charge).

Maybe you're right and it's ticket forgery that this would prevent, but I really question if that's a big driver here of any issues for anyone.