The question is whether the object has value or whether its socially-ascribed non-utility-providing properties hold the value. This is another way of stating that the cardboard of the Mickey Mantle card, or the canvas/pigment combination of the Mona Lisa is trash in and of itself. The only valuable part of the collectible is what people think about it, which exists separately and independently of the thing.
I'll preface this by saying that I'm not really a collector . . . but least in my mind, there is value in the canvas/pigment combination that forms the Mona Lisa - because of who mixed and painted them, because they were physically touched by one of greatest artists of his age. It just doesn't compute for me that the only value of art exists in a receipt and not the work. That's why I usually throw my receipt away, but hang the art on my wall. Even if that art is a knock off duplicate. Do you hang the receipt, or know people who do? Is this some weird collector thing?
Uh, yeah, art collectors absolutely value their certificates of authenticity and will often mount them beside the art piece itself. Other collectors consider this tacky. Some prefer just to hang pieces prominently and then host social events for the sole purpose of having people see that they own a piece, and others find that tacky, but that's kind of a feature of the world of wealth, everyone thinks that *other people's* behaviour is tacky. Either way, in many cases, it's the display of ownership that matters most, often more than the ownership itself. Not always, but often enough.
A HUGE part of the art collecting community is the prestige of ownership. Sure, you can argue that a painting or sculpture is more unique and actually physically rare, but that's usually not the reason someone is willing to pay 500K for it. They're willing to pay for the prestige of having paid for it, and the culture and connections that that implies. Ultra wealthy people aren't just magically more refined in their art taste, the art community generates and curates the talented artists, and then the collectors buy what bubbles to the top of the industry.
Sure, it's great art, but tons of great art will be produced and never be sold to millionaires.
So if what people are buying is actually the experience of buying, and the prestige of having bought, then it makes sense that if someone's social ecosystem consists of blockchain enthusiasts, then NFTs aren't actually that different from buying and displaying art. If all the people whose opinions they care about are impressed with their NFT, then I don't see that as any different than some of the insipid art collectors I've known who would buy a crumpled Wendy's burger wrapper for a million dollars if it would raise their social station.
Now, that doesn't negate the argument that the original art is fundamentally different from the digital art, but what I'm saying is that the originality or even quality of the concrete collectible doesn't actually account for it's market value. If the market value of art and collectibles is primarily set by some kind of collective agreement about what it means to be the person who owns that thing, then that's the same driving force behind the value of NFTs.
Now, I say this as someone who sees all collecting as kind of silly. I have little to no romanticism about old or rare objects. I used to, especially art, but I've long since gotten over it. When I look objectively at my own previous motivations for owning things that I and other people perceived as having value, and the pride I took in that ownership, I can't legitimately say that I was any different than someone who feels pride of ownership for an NFT. Sure, I had a painting, or an antique ring, or a 130 year old book that smelled like spores, I did have those unique, physical things, but once I got over the psychological value assigned to those items, I was able to see them as just items, and start seeing them for their objective value to my day to day life, and not just how *being* the owner of them made me feel.
Now, the physical object obviously does have more value. I will never say that an original painting has the same value as a digital image that can be perfectly copied. What I'm saying is that that value of originality isn't the main driving force behind the price of a lot of crazy high priced goods. The pride of ownership alone accounts for an enormous amount of the value of a lot of high priced items. So you can't just say "well this 8M painting is so valuable because it's a physical painting, but this 8M NFT is worthless". The bulk of that 8M value is how ownership of that item is perceived within society.
NFTs seem stupid to me because I don't circulate in a social environment where anyone would ever care about NFTs. If I spent 10K on an NFT, everyone who's opinion I care about would think I was stupid. But if the people I most wanted to impress in the whole world were impressed by NFTs, then that would be a different matter. Hell, the NFT buyer might look at someone who spends thousands on a Funko Pop doll as fucking nuts.
I used to be the kind of person who wore a giant diamond ring and thought that that mattered because everyone around me thought it mattered. I could barely sell it for 10% of it's purchase price because in actuality, it wasn't worth much. The value in that ring was the pride of ownership and display of what my fiance was willing to buy me, which people around me agreed reflected on my value. That had real value for me in my younger, stupider days when I circulated more among people who cared about that shit. Now it seems insane to me to spend a premium just to display that you spent a premium, for an item that is barely worth a tenth of the purchase price, aka the actual value of the tangible, unique item itself minus the social hype.
So yes, NFTs and physical collectibles are different, but not AS different as they might seem on the surface.