Nah, NFTs don't quite fit the bill. They can act as receipts but they're not good for hosting the product.

I think the spirit of your desire is valid though. What I want to see is the invention of some kind of digital legal-trust structure.

In theory, SAAS providers could produce some kind of "serverless" way to run their SAAS. Trusted cloud providers could host the SAAS past the lifetime of the original company. Users would need to pay for the hosting but the service can live longer than the company given there was a desire.

Legally things could be structured such that this works for closed source SAAS such that it remains closed source. It hits the niche for when just open sourcing the product on the way out isn't feasible.