T206 Honus Wagner baseball card sold for $6.606 million just this August 2021, Pikachu Illustrator, a pokeman card sold for $195,000 in 2019. You can get different Micheal Jordan's basketball card on e-bay ranging from couple of thousands to couple of millions. Sentimental and collectible items have always been part of the human experience. NFTs are not to blame.
Why should pieces of cards with pictures of athletes (or game characters) be worth that much? Why should JPEGs/PNGs be worth that much? Maybe because humans also value things for sentimental reasons just as they do for utilitarian/sustenance reasons.
NFTs only made the act of ownership that was so easy to establish in the physical realm, also possible in the digital realm. It's only natural it will be used for digital arts/collectible culture.
The mistake to avoid, is thinking NFTs are only about digital arts and collectibles. No! they are more than this. The ability to create unique, non fungible digital items that can be provable owned, can be, and is being deployed for other use cases.