"It's just not possible today to build a sophisticated purely digital, autonomous decentralized service/product today."
Granted, Hedera is digital, but from the description in the link you posted it's neither autonomous nor decentralized. "Target and General Mills" may have access to it, but I certainly can't post a "50% off my hand knitted sweater"-Coupon to it. I may also need some convincing that Hedera users are able to verify the cryptographic integrity of a coupon without running "any computer".
"Ignoring web3, how could you solve this?"
Roughly in the way you describe, with a database. You even go on to say "that's essentially what Hedera does", I fail to see the added benefit of slapping a blockchain/web3/NFT/whatever on top, but maybe I'm just ignorant.
Granted, Hedera is digital, but from the description in the link you posted it's neither autonomous nor decentralized. "Target and General Mills" may have access to it, but I certainly can't post a "50% off my hand knitted sweater"-Coupon to it. I may also need some convincing that Hedera users are able to verify the cryptographic integrity of a coupon without running "any computer".
"Ignoring web3, how could you solve this?"
Roughly in the way you describe, with a database. You even go on to say "that's essentially what Hedera does", I fail to see the added benefit of slapping a blockchain/web3/NFT/whatever on top, but maybe I'm just ignorant.