confidendtial transactions and NFTs don't really change the consensus mechanism. They just make the currency fungible or expose the latent non-fungibility.
Etherium is a database. It's a database that contains scripts (not unlike bitcoin) that some computers can run if they want to determine the balance of accounts.
Etherium itself is not a computer, that's marketing speak.
Stripe kinda does have use for this it turn their platform into a much more powerful tool where you can do extremely sophisticated economy based financial automation on your funds held with stripe. Essentially you get some crazy good developer experience which is not possible on tradfi rails.
udev is probably referencing smart contracts(which turn blockchains from shared dbs to shared state-machines), and zk(which allows for cryptographic guarantees of arbitrary computation, and facts about said computation without revealing details of computation). Those are two major innovations on the tech side, there's also rollups, blobs, and a whole host of other interesting developments in the EVM(ethereum virtual machine) ecosystem.
