Why use databases at all? Use a txt file. Digital ownership and potential for profit are the value propositions. Most users probably don't care about the security, decentralization or databases at all.
Why use software at all? Use a paper title registry. Ownership and potential for profit are the value propositions. Most users don't care about decentralization or file formats at all (disagree with your premise on security). Oh wait - that's how the actual Olive Gardens are owned ;)
why use a registry at all? print NFTs on paper and mail it to the collectors.
Authenticity of physical collector's items is a big deal for some people. Some car manufacturers have discontinued providing certificates of authenticity for classic cars because they are afraid of being held responsible for counterfeit stampings and such (one assumes). I don't know specifically how NFTs can help with this, but if they're good for anything...
Why use NFTs at all? Just sell the originals!
And thus we have come full circle.
Why have paper. Verbal contracts are good as them...