Art is special in the sense that there are a lot of forgeries on the physical product, and the it's the physical product that drives the ownership-document, not the other way around.
Take ownership of a piece of land for example. It is the document that is the main driver of the ownership. And no forgery on the land itself can occur, only on the document. And forgery on the document is rare because it is centrally stored by land registry. With cars it's a bit less like that, but still the forgery will occur on the document, not the car.
Right now, when you want to transfer ownership of land, you need to pay an expensive notary to do the transfer. And even then the transfer is not atomic. Large sums of money still take several days to clear over separate banks. If we would live in a blockchain world where ownership of land is stored in the blockchain, and you could pay with cryptocurrency, you actually don't need any notary to do the transfer. A smart contract can verify that all is in place (correct ownership and correct sum of money), and to the transfer of both atomic. With land this might seem strange to you, but with cars this would make perfect sense.
Buying and selling a car is not risk free. Is the money forged? Will he wire-transfer the money? Will I get the ownership document after I pay? Is this the correct ownership document of this car? etc. In the future, the smart contract that does the transfer of ownership could also include the car-key, when this is stored in your smartphone or fingerprint based, instead of a physical key.
To really see the value of blockchain application, look at what notaries and escrow services are doing, and append 'way cheaper' and 'algorithmically correct' to it. I like to comparison of snail mail to email. The latter is free, and more reliable in delivery. Sure the first one still has benefits over email, but which one are you using the most?
Dismissing all blockchain application because one startup didn't do proper verification seems stupid to me, and is in a niche that is less benenicial for blockchains. Like I said, look at what notaries and escrow services are doing, combine that with ownership documents, cryptocurrencies and smart contracts, and see what happens.