if you think about it in the long-term, the rewards eventually go to zero and there's no incentive for any of the miners to mine and the whole thing collapses
Satoshi’s vision was for Bitcoin to be used as digital cash[1], so that transaction demand would be enough to sustain the security of the system. Since the “cash” use case has fallen away to the “store of value” use case, it seems a bit dubious.
Transaction costs have recently gone up because of ordinals and NFTs so we’ll see if that sticks.
[1] the Bitcoin paper was called “Bitcoin: a Peer-to-Peer Electronic Cash System”
But I agree that the NFT thing is really a side-effect of fees being low (thus, cheap distributed storage) which probably at best provides a price floor, rather than a sustainable source of revenue.