Is there any market pressure that will demand a change to the cryptographic hash? Is any of the current speculation concerned in any way about the content hosted at the URL, or just the current value of the NFT and what you can sell it for.
There is. Not from the entire space, but there's a bit of street cred you get by being entirely 'on-chain', as they say.
Within the smart contracts themselves is a read function for that content uri that provides all the data needed (from what I've seen, a hashed string) to generate an .svg file. But it obviously taxes the system and costs a lot more in gas fees (not to read it, that doesn't cost gas fees, but to deploy the contracts and mint), especially the more complex those are, which is why you mostly see it with 8-bit or very low-res artwork.
Cryptopunks being the most well-known (and also the most valuable) NFT project is all on-chain, and Anonymice being the most open and forked project that does this. EtherOrcs does it a little differently but is also on-chain and has completely open contracts you can refer to as well.
There's quite a few more besides this, but I don't know what percent it is, probably pretty small. Some people won't buy anything that's not entirely on-chain. But you're right that most people don't really care, they just care about the price or the image.
I've been digging through the Anonymice and EtherOrcs contracts to get a better understanding of the different approaches they took (and I still wouldn't say I completely understand it yet). It's pretty interesting, though.
EDIT: Sorry, you only said cryptographic hash. Cryptopunks started by providing that, but then moved to entirely on-chain (so above and beyond that), where you could query and get a full SVG file or stream of pixels for any given image directly from the contract.
