There's no such thing as digital scarcity. It's only artificial scarcity, and for that you need something to control the supply.
Anyone can copy the asset. Anyone can also create another NFT to the same asset. So which token is the "real" one? That's the centralized scarcity that's required, which really just added a layer of indirection without solving for anything.
> "spending hundreds of thousands of dollars on artwork or signed sports memorabilia because of the utlity"
Again, this isn't about utility. It's about intrinsic value. Physical goods have a single original object which gives them value that digital items don't.