Ok, I will bite since I like hypothetical discussions to broaden our horizon. I do not believe Grin needs to ‘save’ anyone, it is just a system that will compete with all other systems out there and like all systems, even Grin is not perfect (although very beautiful and elegant IMO). I do like thinking how a coin system can be mixed online and offline. So lets brainstorm 
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One idea that is already going around where you do not need to interact via internet to transfer funds, until claimed is Grin vouchers, basically just giving someone the private key-as QR code:
MW/Grin Workshop+Hackaton in Istanbul - #17 by Anynomous
The problem is that you would not have a payment proof, and to claim it, you would still need an internet connection since any transaction in the end need to happen on-chain. Most importantly, since the data for a grin-voucher is not protected, there is no-way to prove no double spend is happened since a user could simply give/trade/cell the voucher to multiple people. A grin voucher without protection cannot provide the qualities for offline money because of these weaknesses. -
Let’s try again. What if we would transfer Grin vouchers, as QR code, or via NFC-chip. We would still have the problem of double spend and multiple users claiming the funds, unless we can somehow restrict access to the privat-key to the last user who holds the coin/chip at a certain time/block-height.
Meaning we should make each coin a small hardware-wallet chip. First, anyone should be able to verify the coins are there, by giving free access to the Public-key on the hardware wallet, anyone with a copy of the blockchain from a time after creation (just a static copy of the block chain of 2-3 GB, no internet needed) could prove the funds are there and such recognize the value of the coins. Secondly, by using a relative-lock height, we can prove the funds linked to the private key are locked for a couple of years until they can be claimed back.
Thirdly, we would need to restrict access to the private-key by having the pin/password to access the private-key to only be release at a certain block-height after a couple of years. We can make sure only the holder of the chip/key at the time the relative-time lock has access to the private-keys and as such ability to claim the funds. I am not certain about this one, it should be something like a pin/password that is only revealed at a certain block height, yet it should be known at the time of creating these hardware coins. Maybe some sort of stealth transaction with a time-lock? Any ideas?
One last remaining issue is that it should be proven the creators of these coins are not evil since they had access to all factors when they created these coins. I think this last problem of having to trust a central authority is the hardest to solve. In the end we would want the system to be proven and decentralized and not bound to a central authority who could claim all funds themselves when the lock height has been met.